diff --git a/beacon-chain/sync/initial-sync/blocks_fetcher.go b/beacon-chain/sync/initial-sync/blocks_fetcher.go
index 8e877b9b7f..b03322843e 100644
--- a/beacon-chain/sync/initial-sync/blocks_fetcher.go
+++ b/beacon-chain/sync/initial-sync/blocks_fetcher.go
@@ -356,18 +356,22 @@ func (f *blocksFetcher) handleRequest(ctx context.Context, start primitives.Slot
 // It returns the peer ID from which blobs were fetched (if any).
 func (f *blocksFetcher) fetchSidecars(ctx context.Context, pid peer.ID, peers []peer.ID, bwScs []blocks.BlockWithROSidecars) (peer.ID, error) {
 	samplesPerSlot := params.BeaconConfig().SamplesPerSlot
+	count := len(bwScs)
 
-	if len(bwScs) == 0 {
+	if count == 0 {
 		return "", nil
 	}
 
-	// Find the first block with a slot greater than or equal to the first Fulu slot.
-	firstFuluIndex := sort.Search(len(bwScs), func(i int) bool {
-		return bwScs[i].Block.Version() >= version.Fulu
-	})
+	preFuluBlocks, postFuluBlocks := make([]blocks.BlockWithROSidecars, 0, count), make([]blocks.BlockWithROSidecars, 0, count)
 
-	preFuluBlocks := bwScs[:firstFuluIndex]
-	postFuluBlocks := bwScs[firstFuluIndex:]
+	for _, bwSc := range bwScs {
+		if bwSc.Block.Version() >= version.Fulu {
+			postFuluBlocks = append(postFuluBlocks, bwSc)
+			continue
+		}
+
+		preFuluBlocks = append(preFuluBlocks, bwSc)
+	}
 
 	var (
 		blobsPid peer.ID