diff --git a/client/jsonrpc/arbitrum_nitro.go b/client/jsonrpc/arbitrum_nitro.go
index 7208666..aeb9b6a 100644
--- a/client/jsonrpc/arbitrum_nitro.go
+++ b/client/jsonrpc/arbitrum_nitro.go
@@ -33,75 +33,48 @@ func (c *ArbitrumNitroClient) BlockByNumber(ctx context.Context, blockNumber int
 
 	blockNumberHex := fmt.Sprintf("0x%x", blockNumber)
 
-	methods := []string{
-		"eth_getBlockByNumber",
-		"debug_traceBlockByNumber",
-	}
-	methodArgs := map[string][]any{
-		"eth_getBlockByNumber":     {blockNumberHex, true},
-		"debug_traceBlockByNumber": {blockNumberHex, map[string]string{"tracer": "callTracer"}},
-	}
-	group, groupCtx := errgroup.WithContext(ctx)
-	results := make([]*bytes.Buffer, len(methods))
-	for i, method := range methods {
-		results[i] = c.bufPool.Get().(*bytes.Buffer)
-		defer c.putBuffer(results[i])
+	results := make([]*bytes.Buffer, 0, 8)
 
-		group.Go(func() error {
-			errCh := make(chan error, 1)
-			c.wrkPool.Submit(func() {
-				defer close(errCh)
-				err := c.getResponseBody(groupCtx, method, methodArgs[method], results[i])
-				if err != nil {
-					c.log.Error("Failed to get response for jsonRPC",
-						"blockNumber", blockNumber,
-						"method", method,
-						"error", err,
-					)
-					errCh <- err
-				} else {
-					errCh <- nil
-				}
-			})
-			return <-errCh
-		})
-	}
-
-	if err := group.Wait(); err != nil {
+	// eth_getBlockByNumber and extract the transaction hashes
+	getBlockNumberResponse := c.bufPool.Get().(*bytes.Buffer)
+	defer c.putBuffer(getBlockNumberResponse)
+	results = append(results, getBlockNumberResponse)
+	err := c.getResponseBody(ctx, "eth_getBlockByNumber", []any{blockNumberHex, true}, getBlockNumberResponse)
+	if err != nil {
+		c.log.Error("Failed to get response for jsonRPC",
+			"blockNumber", blockNumber,
+			"method", "eth_getBlockByNumber",
+			"error", err,
+		)
 		return models.RPCBlock{}, err
 	}
-
-	txHashes, err := getTransactionHashes(results[0].Bytes())
+	txHashes, err := getTransactionHashes(getBlockNumberResponse.Bytes())
 	if err != nil {
 		return models.RPCBlock{}, err
 	}
 
 	c.log.Debug("BlockByNumber", "blockNumber", blockNumber, "txCount", len(txHashes))
-	group, groupCtx = errgroup.WithContext(ctx)
+	group, groupCtx := errgroup.WithContext(ctx)
+
+	// debug_traceBlockByNumber
+	result := c.bufPool.Get().(*bytes.Buffer)
+	defer c.putBuffer(result)
+	results = append(results, result)
+
+	c.GroupedJSONrpc(
+		groupCtx,
+		group,
+		"debug_traceBlockByNumber",
+		[]any{blockNumberHex, map[string]string{"tracer": "callTracer"}},
+		result,
+		blockNumber,
+	)
 	for _, tx := range txHashes {
 		result := c.bufPool.Get().(*bytes.Buffer)
 		defer c.putBuffer(result)
-
 		results = append(results, result)
-		group.Go(func() error {
-			errCh := make(chan error, 1)
-			c.wrkPool.Submit(func() {
-				defer close(errCh)
-				err := c.getResponseBody(groupCtx, "eth_getTransactionReceipt", []any{tx.Hash}, result)
-				if err != nil {
-					c.log.Error("Failed to get response for jsonRPC",
-						"blockNumber", blockNumber,
-						"method", "eth_getTransactionReceipt",
-						"txHash", tx.Hash,
-						"error", err,
-					)
-					errCh <- err
-				} else {
-					errCh <- nil
-				}
-			})
-			return <-errCh
-		})
+
+		c.GroupedJSONrpc(groupCtx, group, "eth_getTransactionReceipt", []any{tx.Hash}, result, blockNumber)
 	}
 	if err := group.Wait(); err != nil {
 		return models.RPCBlock{}, err
diff --git a/client/jsonrpc/client.go b/client/jsonrpc/client.go
index 37da897..7aa637f 100644
--- a/client/jsonrpc/client.go
+++ b/client/jsonrpc/client.go
@@ -14,6 +14,7 @@ import (
 	"github.com/duneanalytics/blockchain-ingester/models"
 	"github.com/hashicorp/go-retryablehttp"
 	"github.com/panjf2000/ants/v2"
+	"golang.org/x/sync/errgroup"
 )
 
 type BlockchainClient interface {
@@ -110,6 +111,37 @@ func (c *rpcClient) LatestBlockNumber() (int64, error) {
 	return hexutils.IntFromHex(resp.Result)
 }
 
+// GroupedJSONrpc is a helper function to spawn multiple calls belonging to the same group.
+// errors are propagated to the errgroup.
+// concurrency is managed by the worker pool.
+func (c *rpcClient) GroupedJSONrpc(
+	ctx context.Context,
+	group *errgroup.Group,
+	method string,
+	args []any,
+	output *bytes.Buffer,
+	debugBlockNumber int64,
+) {
+	group.Go(func() error {
+		errCh := make(chan error, 1)
+		c.wrkPool.Submit(func() {
+			defer close(errCh)
+			err := c.getResponseBody(ctx, method, args, output)
+			if err != nil {
+				c.log.Error("Failed to get response for jsonRPC",
+					"blockNumber", debugBlockNumber,
+					"method", method,
+					"error", err,
+				)
+				errCh <- err
+			} else {
+				errCh <- nil
+			}
+		})
+		return <-errCh
+	})
+}
+
 // getResponseBody sends a request to the server and returns the response body
 func (c *rpcClient) getResponseBody(
 	ctx context.Context, method string, params []interface{}, output *bytes.Buffer,
diff --git a/client/jsonrpc/opstack.go b/client/jsonrpc/opstack.go
index 2f9858e..31de45e 100644
--- a/client/jsonrpc/opstack.go
+++ b/client/jsonrpc/opstack.go
@@ -49,24 +49,7 @@ func (c *OpStackClient) BlockByNumber(ctx context.Context, blockNumber int64) (m
 		results[i] = c.bufPool.Get().(*bytes.Buffer)
 		defer c.putBuffer(results[i])
 
-		group.Go(func() error {
-			errCh := make(chan error, 1)
-			c.wrkPool.Submit(func() {
-				defer close(errCh)
-				err := c.getResponseBody(ctx, method, methodArgs[method], results[i])
-				if err != nil {
-					c.log.Error("Failed to get response for jsonRPC",
-						"blockNumber", blockNumber,
-						"method", method,
-						"error", err,
-					)
-					errCh <- err
-				} else {
-					errCh <- nil
-				}
-			})
-			return <-errCh
-		})
+		c.GroupedJSONrpc(ctx, group, method, methodArgs[method], results[i], blockNumber)
 	}
 
 	if err := group.Wait(); err != nil {