diff --git a/x-pack/plugins/apm/server/lib/transaction_groups/__snapshots__/fetcher.test.ts.snap b/x-pack/plugins/apm/server/lib/transaction_groups/__snapshots__/fetcher.test.ts.snap
index 9e180f3fcdb5d..07f8bf59f53a0 100644
--- a/x-pack/plugins/apm/server/lib/transaction_groups/__snapshots__/fetcher.test.ts.snap
+++ b/x-pack/plugins/apm/server/lib/transaction_groups/__snapshots__/fetcher.test.ts.snap
@@ -26,6 +26,9 @@ Array [
                 "top_hits": Object {
                   "size": 1,
                   "sort": Array [
+                    Object {
+                      "_score": "desc",
+                    },
                     Object {
                       "@timestamp": Object {
                         "order": "desc",
diff --git a/x-pack/plugins/apm/server/lib/transaction_groups/fetcher.ts b/x-pack/plugins/apm/server/lib/transaction_groups/fetcher.ts
index 9ab287402c561..2a534aa3315f1 100644
--- a/x-pack/plugins/apm/server/lib/transaction_groups/fetcher.ts
+++ b/x-pack/plugins/apm/server/lib/transaction_groups/fetcher.ts
@@ -64,7 +64,10 @@ export function transactionGroupsFetcher(
             sample: {
               top_hits: {
                 size: 1,
-                sort: [{ '@timestamp': { order: 'desc' } }]
+                sort: [
+                  { _score: 'desc' }, // sort by _score to ensure that buckets with sampled:true ends up on top
+                  { '@timestamp': { order: 'desc' } }
+                ]
               }
             },
             avg: { avg: { field: TRANSACTION_DURATION } },