diff --git a/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js b/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js
index 1c65501f7b3824..411451a2feade7 100644
--- a/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js
+++ b/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js
@@ -437,7 +437,7 @@ describe('ReactDOMServerPartialHydration', () => {
     expect(container.innerHTML).toContain('<div>Sibling</div>');
   });
 
-  it('recovers when server rendered additional nodes', async () => {
+  it('recovers with client render when server rendered additional nodes at suspense root', async () => {
     const ref = React.createRef();
     function App({hasB}) {
       return (
@@ -462,15 +462,135 @@ describe('ReactDOMServerPartialHydration', () => {
     expect(container.innerHTML).toContain('<span>B</span>');
     expect(ref.current).toBe(null);
 
-    ReactDOM.hydrateRoot(container, <App hasB={false} />);
     expect(() => {
-      Scheduler.unstable_flushAll();
+      act(() => {
+        ReactDOM.hydrateRoot(container, <App hasB={false} />);
+      });
     }).toErrorDev('Did not expect server HTML to contain a <span> in <div>');
+
     jest.runAllTimers();
 
     expect(container.innerHTML).toContain('<span>A</span>');
     expect(container.innerHTML).not.toContain('<span>B</span>');
-    expect(ref.current).toBe(span);
+
+    if (gate(flags => flags.enableClientRenderFallbackOnHydrationMismatch)) {
+      expect(ref.current).not.toBe(span);
+    } else {
+      expect(ref.current).toBe(span);
+    }
+  });
+
+  it('recovers with client render when server rendered additional nodes at suspense root after unsuspending', async () => {
+    const ref = React.createRef();
+    function App({hasB}) {
+      return (
+        <div>
+          <Suspense fallback="Loading...">
+            <Suspender />
+            <span ref={ref}>A</span>
+            {hasB ? <span>B</span> : null}
+          </Suspense>
+          <div>Sibling</div>
+        </div>
+      );
+    }
+
+    let shouldSuspend = false;
+    let resolve;
+    const promise = new Promise(res => {
+      resolve = () => {
+        shouldSuspend = false;
+        res();
+      };
+    });
+    function Suspender() {
+      if (shouldSuspend) {
+        throw promise;
+      }
+      return <div />;
+    }
+
+    const finalHTML = ReactDOMServer.renderToString(<App hasB={true} />);
+
+    const container = document.createElement('div');
+    container.innerHTML = finalHTML;
+
+    const span = container.getElementsByTagName('span')[0];
+
+    expect(container.innerHTML).toContain('<span>A</span>');
+    expect(container.innerHTML).toContain('<span>B</span>');
+    expect(ref.current).toBe(null);
+
+    shouldSuspend = true;
+    act(() => {
+      ReactDOM.hydrateRoot(container, <App hasB={false} />);
+    });
+
+    spyOnDev(console, 'error');
+
+    resolve();
+    await promise;
+    Scheduler.unstable_flushAll();
+    await null;
+    jest.runAllTimers();
+
+    expect(container.innerHTML).toContain('<span>A</span>');
+    expect(container.innerHTML).not.toContain('<span>B</span>');
+    if (gate(flags => flags.enableClientRenderFallbackOnHydrationMismatch)) {
+      expect(ref.current).not.toBe(span);
+    } else {
+      expect(ref.current).toBe(span);
+    }
+
+    expect(console.error.calls.count()).toBe(1);
+    const errorArgs = console.error.calls.first().args;
+    expect(errorArgs[0]).toBe(
+      'Warning: Did not expect server HTML to contain a <%s> in <%s>.%s',
+    );
+    expect(errorArgs[1]).toBe('span');
+    expect(errorArgs[2]).toBe('div');
+  });
+
+  it('recovers with client render when server rendered additional nodes deep inside suspense root', async () => {
+    const ref = React.createRef();
+    function App({hasB}) {
+      return (
+        <div>
+          <Suspense fallback="Loading...">
+            <div>
+              <span ref={ref}>A</span>
+              {hasB ? <span>B</span> : null}
+            </div>
+          </Suspense>
+          <div>Sibling</div>
+        </div>
+      );
+    }
+
+    const finalHTML = ReactDOMServer.renderToString(<App hasB={true} />);
+
+    const container = document.createElement('div');
+    container.innerHTML = finalHTML;
+
+    const span = container.getElementsByTagName('span')[0];
+
+    expect(container.innerHTML).toContain('<span>A</span>');
+    expect(container.innerHTML).toContain('<span>B</span>');
+    expect(ref.current).toBe(null);
+
+    expect(() => {
+      act(() => {
+        ReactDOM.hydrateRoot(container, <App hasB={false} />);
+      });
+    }).toErrorDev('Did not expect server HTML to contain a <span> in <div>');
+
+    expect(container.innerHTML).toContain('<span>A</span>');
+    expect(container.innerHTML).not.toContain('<span>B</span>');
+    if (gate(flags => flags.enableClientRenderFallbackOnHydrationMismatch)) {
+      expect(ref.current).not.toBe(span);
+    } else {
+      expect(ref.current).toBe(span);
+    }
   });
 
   it('calls the onDeleted hydration callback if the parent gets deleted', async () => {
diff --git a/packages/react-reconciler/src/ReactFiberCompleteWork.new.js b/packages/react-reconciler/src/ReactFiberCompleteWork.new.js
index 91c564dd465ba5..21f86645735dbb 100644
--- a/packages/react-reconciler/src/ReactFiberCompleteWork.new.js
+++ b/packages/react-reconciler/src/ReactFiberCompleteWork.new.js
@@ -29,7 +29,10 @@ import type {
 import type {SuspenseContext} from './ReactFiberSuspenseContext.new';
 import type {OffscreenState} from './ReactFiberOffscreenComponent';
 import type {Cache, SpawnedCachePool} from './ReactFiberCacheComponent.new';
-import {enableSuspenseAvoidThisFallback} from 'shared/ReactFeatureFlags';
+import {
+  enableClientRenderFallbackOnHydrationMismatch,
+  enableSuspenseAvoidThisFallback,
+} from 'shared/ReactFeatureFlags';
 
 import {resetWorkInProgressVersions as resetMutableSourceWorkInProgressVersions} from './ReactMutableSource.new';
 
@@ -74,6 +77,9 @@ import {
   StaticMask,
   MutationMask,
   Passive,
+  Incomplete,
+  ShouldCapture,
+  ForceClientRender,
 } from './ReactFiberFlags';
 
 import {
@@ -120,9 +126,11 @@ import {
   prepareToHydrateHostInstance,
   prepareToHydrateHostTextInstance,
   prepareToHydrateHostSuspenseInstance,
+  warnDeleteNextHydratableInstance,
   popHydrationState,
   resetHydrationState,
   getIsHydrating,
+  hasMore,
 } from './ReactFiberHydrationContext.new';
 import {
   enableSuspenseCallback,
@@ -828,7 +836,6 @@ function completeWork(
   // to the current tree provider fiber is just as fast and less error-prone.
   // Ideally we would have a special version of the work loop only
   // for hydration.
-  popTreeContext(workInProgress);
   switch (workInProgress.tag) {
     case IndeterminateComponent:
     case LazyComponent:
@@ -840,9 +847,11 @@ function completeWork(
     case Profiler:
     case ContextConsumer:
     case MemoComponent:
+      popTreeContext(workInProgress);
       bubbleProperties(workInProgress);
       return null;
     case ClassComponent: {
+      popTreeContext(workInProgress);
       const Component = workInProgress.type;
       if (isLegacyContextProvider(Component)) {
         popLegacyContext(workInProgress);
@@ -852,6 +861,23 @@ function completeWork(
     }
     case HostRoot: {
       const fiberRoot = (workInProgress.stateNode: FiberRoot);
+      if (current === null || current.child === null) {
+        // If we hydrated, pop so that we can delete any remaining children
+        // that weren't hydrated.
+        const wasHydrated = popHydrationState(workInProgress);
+        if (wasHydrated) {
+          // If we hydrated, then we'll need to schedule an update for
+          // the commit side-effects on the root.
+          markUpdate(workInProgress);
+        } else if (!fiberRoot.isDehydrated) {
+          // Schedule an effect to clear this container at the start of the next commit.
+          // This handles the case of React rendering into a container with previous children.
+          // It's also safe to do for updates too, because current.child would only be null
+          // if the previous render was null (so the container would already be empty).
+          workInProgress.flags |= Snapshot;
+        }
+      }
+      popTreeContext(workInProgress);
       if (enableCache) {
         popRootCachePool(fiberRoot, renderLanes);
 
@@ -873,27 +899,13 @@ function completeWork(
         fiberRoot.context = fiberRoot.pendingContext;
         fiberRoot.pendingContext = null;
       }
-      if (current === null || current.child === null) {
-        // If we hydrated, pop so that we can delete any remaining children
-        // that weren't hydrated.
-        const wasHydrated = popHydrationState(workInProgress);
-        if (wasHydrated) {
-          // If we hydrated, then we'll need to schedule an update for
-          // the commit side-effects on the root.
-          markUpdate(workInProgress);
-        } else if (!fiberRoot.isDehydrated) {
-          // Schedule an effect to clear this container at the start of the next commit.
-          // This handles the case of React rendering into a container with previous children.
-          // It's also safe to do for updates too, because current.child would only be null
-          // if the previous render was null (so the container would already be empty).
-          workInProgress.flags |= Snapshot;
-        }
-      }
       updateHostContainer(current, workInProgress);
       bubbleProperties(workInProgress);
       return null;
     }
     case HostComponent: {
+      const wasHydrated = popHydrationState(workInProgress);
+      popTreeContext(workInProgress);
       popHostContext(workInProgress);
       const rootContainerInstance = getRootHostContainer();
       const type = workInProgress.type;
@@ -928,7 +940,6 @@ function completeWork(
         // "stack" as the parent. Then append children as we go in beginWork
         // or completeWork depending on whether we want to add them top->down or
         // bottom->up. Top->down is faster in IE11.
-        const wasHydrated = popHydrationState(workInProgress);
         if (wasHydrated) {
           // TODO: Move this and createInstance step into the beginPhase
           // to consolidate.
@@ -981,6 +992,7 @@ function completeWork(
       return null;
     }
     case HostText: {
+      popTreeContext(workInProgress);
       const newText = newProps;
       if (current && workInProgress.stateNode != null) {
         const oldText = current.memoizedProps;
@@ -1017,14 +1029,27 @@ function completeWork(
       return null;
     }
     case SuspenseComponent: {
-      popSuspenseContext(workInProgress);
       const nextState: null | SuspenseState = workInProgress.memoizedState;
-
       if (enableSuspenseServerRenderer) {
+        if (
+          enableClientRenderFallbackOnHydrationMismatch &&
+          hasMore() &&
+          (workInProgress.flags & DidCapture) === NoFlags
+        ) {
+          warnDeleteNextHydratableInstance(workInProgress);
+          resetHydrationState();
+          workInProgress.flags |=
+            ForceClientRender | Incomplete | ShouldCapture;
+          popTreeContext(workInProgress);
+          popSuspenseContext(workInProgress);
+          return workInProgress;
+        }
         if (nextState !== null && nextState.dehydrated !== null) {
           // We might be inside a hydration state the first time we're picking up this
           // Suspense boundary, and also after we've reentered it for further hydration.
           const wasHydrated = popHydrationState(workInProgress);
+          popTreeContext(workInProgress);
+          popSuspenseContext(workInProgress);
           if (current === null) {
             if (!wasHydrated) {
               throw new Error(
@@ -1091,6 +1116,8 @@ function completeWork(
         ) {
           transferActualDuration(workInProgress);
         }
+        popTreeContext(workInProgress);
+        popSuspenseContext(workInProgress);
         // Don't bubble properties in this case.
         return workInProgress;
       }
@@ -1103,6 +1130,8 @@ function completeWork(
         const prevState: null | SuspenseState = current.memoizedState;
         prevDidTimeout = prevState !== null;
       }
+      popTreeContext(workInProgress);
+      popSuspenseContext(workInProgress);
 
       if (enableCache && nextDidTimeout) {
         const offscreenFiber: Fiber = (workInProgress.child: any);
@@ -1207,6 +1236,7 @@ function completeWork(
       return null;
     }
     case HostPortal:
+      popTreeContext(workInProgress);
       popHostContainer(workInProgress);
       updateHostContainer(current, workInProgress);
       if (current === null) {
@@ -1215,12 +1245,14 @@ function completeWork(
       bubbleProperties(workInProgress);
       return null;
     case ContextProvider:
+      popTreeContext(workInProgress);
       // Pop provider fiber
       const context: ReactContext<any> = workInProgress.type._context;
       popProvider(context, workInProgress);
       bubbleProperties(workInProgress);
       return null;
     case IncompleteClassComponent: {
+      popTreeContext(workInProgress);
       // Same as class component case. I put it down here so that the tags are
       // sequential to ensure this switch is compiled to a jump table.
       const Component = workInProgress.type;
@@ -1231,6 +1263,7 @@ function completeWork(
       return null;
     }
     case SuspenseListComponent: {
+      popTreeContext(workInProgress);
       popSuspenseContext(workInProgress);
 
       const renderState: null | SuspenseListRenderState =
@@ -1440,6 +1473,7 @@ function completeWork(
       return null;
     }
     case ScopeComponent: {
+      popTreeContext(workInProgress);
       if (enableScopeAPI) {
         if (current === null) {
           const scopeInstance: ReactScopeInstance = createScopeInstance();
@@ -1464,6 +1498,7 @@ function completeWork(
     }
     case OffscreenComponent:
     case LegacyHiddenComponent: {
+      popTreeContext(workInProgress);
       popRenderLanes(workInProgress);
       const nextState: OffscreenState | null = workInProgress.memoizedState;
       const nextIsHidden = nextState !== null;
@@ -1532,6 +1567,7 @@ function completeWork(
       return null;
     }
     case CacheComponent: {
+      popTreeContext(workInProgress);
       if (enableCache) {
         let previousCache: Cache | null = null;
         if (workInProgress.alternate !== null) {
diff --git a/packages/react-reconciler/src/ReactFiberCompleteWork.old.js b/packages/react-reconciler/src/ReactFiberCompleteWork.old.js
index ea994583cfe8dd..9830f51a10fa7a 100644
--- a/packages/react-reconciler/src/ReactFiberCompleteWork.old.js
+++ b/packages/react-reconciler/src/ReactFiberCompleteWork.old.js
@@ -29,7 +29,10 @@ import type {
 import type {SuspenseContext} from './ReactFiberSuspenseContext.old';
 import type {OffscreenState} from './ReactFiberOffscreenComponent';
 import type {Cache, SpawnedCachePool} from './ReactFiberCacheComponent.old';
-import {enableSuspenseAvoidThisFallback} from 'shared/ReactFeatureFlags';
+import {
+  enableClientRenderFallbackOnHydrationMismatch,
+  enableSuspenseAvoidThisFallback,
+} from 'shared/ReactFeatureFlags';
 
 import {resetWorkInProgressVersions as resetMutableSourceWorkInProgressVersions} from './ReactMutableSource.old';
 
@@ -74,6 +77,9 @@ import {
   StaticMask,
   MutationMask,
   Passive,
+  Incomplete,
+  ShouldCapture,
+  ForceClientRender,
 } from './ReactFiberFlags';
 
 import {
@@ -120,9 +126,11 @@ import {
   prepareToHydrateHostInstance,
   prepareToHydrateHostTextInstance,
   prepareToHydrateHostSuspenseInstance,
+  warnDeleteNextHydratableInstance,
   popHydrationState,
   resetHydrationState,
   getIsHydrating,
+  hasMore,
 } from './ReactFiberHydrationContext.old';
 import {
   enableSuspenseCallback,
@@ -828,7 +836,6 @@ function completeWork(
   // to the current tree provider fiber is just as fast and less error-prone.
   // Ideally we would have a special version of the work loop only
   // for hydration.
-  popTreeContext(workInProgress);
   switch (workInProgress.tag) {
     case IndeterminateComponent:
     case LazyComponent:
@@ -840,9 +847,11 @@ function completeWork(
     case Profiler:
     case ContextConsumer:
     case MemoComponent:
+      popTreeContext(workInProgress);
       bubbleProperties(workInProgress);
       return null;
     case ClassComponent: {
+      popTreeContext(workInProgress);
       const Component = workInProgress.type;
       if (isLegacyContextProvider(Component)) {
         popLegacyContext(workInProgress);
@@ -852,6 +861,23 @@ function completeWork(
     }
     case HostRoot: {
       const fiberRoot = (workInProgress.stateNode: FiberRoot);
+      if (current === null || current.child === null) {
+        // If we hydrated, pop so that we can delete any remaining children
+        // that weren't hydrated.
+        const wasHydrated = popHydrationState(workInProgress);
+        if (wasHydrated) {
+          // If we hydrated, then we'll need to schedule an update for
+          // the commit side-effects on the root.
+          markUpdate(workInProgress);
+        } else if (!fiberRoot.isDehydrated) {
+          // Schedule an effect to clear this container at the start of the next commit.
+          // This handles the case of React rendering into a container with previous children.
+          // It's also safe to do for updates too, because current.child would only be null
+          // if the previous render was null (so the container would already be empty).
+          workInProgress.flags |= Snapshot;
+        }
+      }
+      popTreeContext(workInProgress);
       if (enableCache) {
         popRootCachePool(fiberRoot, renderLanes);
 
@@ -873,27 +899,13 @@ function completeWork(
         fiberRoot.context = fiberRoot.pendingContext;
         fiberRoot.pendingContext = null;
       }
-      if (current === null || current.child === null) {
-        // If we hydrated, pop so that we can delete any remaining children
-        // that weren't hydrated.
-        const wasHydrated = popHydrationState(workInProgress);
-        if (wasHydrated) {
-          // If we hydrated, then we'll need to schedule an update for
-          // the commit side-effects on the root.
-          markUpdate(workInProgress);
-        } else if (!fiberRoot.isDehydrated) {
-          // Schedule an effect to clear this container at the start of the next commit.
-          // This handles the case of React rendering into a container with previous children.
-          // It's also safe to do for updates too, because current.child would only be null
-          // if the previous render was null (so the container would already be empty).
-          workInProgress.flags |= Snapshot;
-        }
-      }
       updateHostContainer(current, workInProgress);
       bubbleProperties(workInProgress);
       return null;
     }
     case HostComponent: {
+      const wasHydrated = popHydrationState(workInProgress);
+      popTreeContext(workInProgress);
       popHostContext(workInProgress);
       const rootContainerInstance = getRootHostContainer();
       const type = workInProgress.type;
@@ -928,7 +940,6 @@ function completeWork(
         // "stack" as the parent. Then append children as we go in beginWork
         // or completeWork depending on whether we want to add them top->down or
         // bottom->up. Top->down is faster in IE11.
-        const wasHydrated = popHydrationState(workInProgress);
         if (wasHydrated) {
           // TODO: Move this and createInstance step into the beginPhase
           // to consolidate.
@@ -981,6 +992,7 @@ function completeWork(
       return null;
     }
     case HostText: {
+      popTreeContext(workInProgress);
       const newText = newProps;
       if (current && workInProgress.stateNode != null) {
         const oldText = current.memoizedProps;
@@ -1017,14 +1029,23 @@ function completeWork(
       return null;
     }
     case SuspenseComponent: {
-      popSuspenseContext(workInProgress);
       const nextState: null | SuspenseState = workInProgress.memoizedState;
-
       if (enableSuspenseServerRenderer) {
         if (nextState !== null && nextState.dehydrated !== null) {
+          if (enableClientRenderFallbackOnHydrationMismatch && hasMore()) {
+            warnDeleteNextHydratableInstance(workInProgress);
+            resetHydrationState();
+            workInProgress.flags |=
+              ForceClientRender | Incomplete | ShouldCapture;
+            popTreeContext(workInProgress);
+            popSuspenseContext(workInProgress);
+            return workInProgress;
+          }
           // We might be inside a hydration state the first time we're picking up this
           // Suspense boundary, and also after we've reentered it for further hydration.
           const wasHydrated = popHydrationState(workInProgress);
+          popTreeContext(workInProgress);
+          popSuspenseContext(workInProgress);
           if (current === null) {
             if (!wasHydrated) {
               throw new Error(
@@ -1091,6 +1112,8 @@ function completeWork(
         ) {
           transferActualDuration(workInProgress);
         }
+        popTreeContext(workInProgress);
+        popSuspenseContext(workInProgress);
         // Don't bubble properties in this case.
         return workInProgress;
       }
@@ -1104,6 +1127,9 @@ function completeWork(
         prevDidTimeout = prevState !== null;
       }
 
+      popTreeContext(workInProgress);
+      popSuspenseContext(workInProgress);
+
       if (enableCache && nextDidTimeout) {
         const offscreenFiber: Fiber = (workInProgress.child: any);
         let previousCache: Cache | null = null;
@@ -1207,6 +1233,7 @@ function completeWork(
       return null;
     }
     case HostPortal:
+      popTreeContext(workInProgress);
       popHostContainer(workInProgress);
       updateHostContainer(current, workInProgress);
       if (current === null) {
@@ -1215,12 +1242,14 @@ function completeWork(
       bubbleProperties(workInProgress);
       return null;
     case ContextProvider:
+      popTreeContext(workInProgress);
       // Pop provider fiber
       const context: ReactContext<any> = workInProgress.type._context;
       popProvider(context, workInProgress);
       bubbleProperties(workInProgress);
       return null;
     case IncompleteClassComponent: {
+      popTreeContext(workInProgress);
       // Same as class component case. I put it down here so that the tags are
       // sequential to ensure this switch is compiled to a jump table.
       const Component = workInProgress.type;
@@ -1231,6 +1260,7 @@ function completeWork(
       return null;
     }
     case SuspenseListComponent: {
+      popTreeContext(workInProgress);
       popSuspenseContext(workInProgress);
 
       const renderState: null | SuspenseListRenderState =
@@ -1440,6 +1470,7 @@ function completeWork(
       return null;
     }
     case ScopeComponent: {
+      popTreeContext(workInProgress);
       if (enableScopeAPI) {
         if (current === null) {
           const scopeInstance: ReactScopeInstance = createScopeInstance();
@@ -1464,6 +1495,7 @@ function completeWork(
     }
     case OffscreenComponent:
     case LegacyHiddenComponent: {
+      popTreeContext(workInProgress);
       popRenderLanes(workInProgress);
       const nextState: OffscreenState | null = workInProgress.memoizedState;
       const nextIsHidden = nextState !== null;
@@ -1532,6 +1564,7 @@ function completeWork(
       return null;
     }
     case CacheComponent: {
+      popTreeContext(workInProgress);
       if (enableCache) {
         let previousCache: Cache | null = null;
         if (workInProgress.alternate !== null) {
diff --git a/packages/react-reconciler/src/ReactFiberHydrationContext.new.js b/packages/react-reconciler/src/ReactFiberHydrationContext.new.js
index 614c6c9d946ca9..582a39f756e1fa 100644
--- a/packages/react-reconciler/src/ReactFiberHydrationContext.new.js
+++ b/packages/react-reconciler/src/ReactFiberHydrationContext.new.js
@@ -121,7 +121,7 @@ function reenterHydrationStateFromDehydratedSuspenseInstance(
   return true;
 }
 
-function deleteHydratableInstance(
+function warnDeleteHydratableInstance(
   returnFiber: Fiber,
   instance: HydratableInstance,
 ) {
@@ -151,7 +151,13 @@ function deleteHydratableInstance(
         break;
     }
   }
+}
 
+function deleteHydratableInstance(
+  returnFiber: Fiber,
+  instance: HydratableInstance,
+) {
+  warnDeleteHydratableInstance(returnFiber, instance);
   const childToDelete = createFiberFromHostInstanceForDeletion();
   childToDelete.stateNode = instance;
   childToDelete.return = returnFiber;
@@ -539,12 +545,15 @@ function popHydrationState(fiber: Fiber): boolean {
         !shouldSetTextContent(fiber.type, fiber.memoizedProps)))
   ) {
     let nextInstance = nextHydratableInstance;
-    while (nextInstance) {
-      deleteHydratableInstance(fiber, nextInstance);
-      nextInstance = getNextHydratableSibling(nextInstance);
+    if (nextInstance) {
+      warnDeleteNextHydratableInstance(fiber);
+      throwOnHydrationMismatchIfConcurrentMode(fiber);
+      while (nextInstance) {
+        deleteHydratableInstance(fiber, nextInstance);
+        nextInstance = getNextHydratableSibling(nextInstance);
+      }
     }
   }
-
   popToNextHostParent(fiber);
   if (fiber.tag === SuspenseComponent) {
     nextHydratableInstance = skipPastDehydratedSuspenseInstance(fiber);
@@ -556,6 +565,16 @@ function popHydrationState(fiber: Fiber): boolean {
   return true;
 }
 
+function hasMore() {
+  return isHydrating && nextHydratableInstance !== null;
+}
+
+function warnDeleteNextHydratableInstance(fiber: Fiber) {
+  if (nextHydratableInstance) {
+    warnDeleteHydratableInstance(fiber, nextHydratableInstance);
+  }
+}
+
 function resetHydrationState(): void {
   if (!supportsHydration) {
     return;
@@ -581,4 +600,6 @@ export {
   prepareToHydrateHostTextInstance,
   prepareToHydrateHostSuspenseInstance,
   popHydrationState,
+  hasMore,
+  warnDeleteNextHydratableInstance,
 };
diff --git a/packages/react-reconciler/src/ReactFiberHydrationContext.old.js b/packages/react-reconciler/src/ReactFiberHydrationContext.old.js
index b7bca8217d979f..fb2db55b1b57ae 100644
--- a/packages/react-reconciler/src/ReactFiberHydrationContext.old.js
+++ b/packages/react-reconciler/src/ReactFiberHydrationContext.old.js
@@ -121,7 +121,7 @@ function reenterHydrationStateFromDehydratedSuspenseInstance(
   return true;
 }
 
-function deleteHydratableInstance(
+function warnDeleteHydratableInstance(
   returnFiber: Fiber,
   instance: HydratableInstance,
 ) {
@@ -151,7 +151,13 @@ function deleteHydratableInstance(
         break;
     }
   }
+}
 
+function deleteHydratableInstance(
+  returnFiber: Fiber,
+  instance: HydratableInstance,
+) {
+  warnDeleteHydratableInstance(returnFiber, instance);
   const childToDelete = createFiberFromHostInstanceForDeletion();
   childToDelete.stateNode = instance;
   childToDelete.return = returnFiber;
@@ -539,12 +545,15 @@ function popHydrationState(fiber: Fiber): boolean {
         !shouldSetTextContent(fiber.type, fiber.memoizedProps)))
   ) {
     let nextInstance = nextHydratableInstance;
-    while (nextInstance) {
-      deleteHydratableInstance(fiber, nextInstance);
-      nextInstance = getNextHydratableSibling(nextInstance);
+    if (nextInstance) {
+      warnDeleteNextHydratableInstance(fiber);
+      throwOnHydrationMismatchIfConcurrentMode(fiber);
+      while (nextInstance) {
+        deleteHydratableInstance(fiber, nextInstance);
+        nextInstance = getNextHydratableSibling(nextInstance);
+      }
     }
   }
-
   popToNextHostParent(fiber);
   if (fiber.tag === SuspenseComponent) {
     nextHydratableInstance = skipPastDehydratedSuspenseInstance(fiber);
@@ -556,6 +565,16 @@ function popHydrationState(fiber: Fiber): boolean {
   return true;
 }
 
+function hasMore() {
+  return isHydrating && nextHydratableInstance !== null;
+}
+
+function warnDeleteNextHydratableInstance(fiber: Fiber) {
+  if (nextHydratableInstance) {
+    warnDeleteHydratableInstance(fiber, nextHydratableInstance);
+  }
+}
+
 function resetHydrationState(): void {
   if (!supportsHydration) {
     return;
@@ -581,4 +600,6 @@ export {
   prepareToHydrateHostTextInstance,
   prepareToHydrateHostSuspenseInstance,
   popHydrationState,
+  hasMore,
+  warnDeleteNextHydratableInstance,
 };