diff --git a/beacon/sync/src/test/java/tech/pegasys/teku/beacon/sync/fetch/FetchBlobSidecarsTaskTest.java b/beacon/sync/src/test/java/tech/pegasys/teku/beacon/sync/fetch/FetchBlobSidecarsTaskTest.java
index b705e980da7..b3893e92fac 100644
--- a/beacon/sync/src/test/java/tech/pegasys/teku/beacon/sync/fetch/FetchBlobSidecarsTaskTest.java
+++ b/beacon/sync/src/test/java/tech/pegasys/teku/beacon/sync/fetch/FetchBlobSidecarsTaskTest.java
@@ -249,10 +249,11 @@ private List<BlobIdentifier> getBlobIdentifiers(final List<BlobSidecar> blobSide
         .toList();
   }
 
+  @SuppressWarnings("FutureReturnValueIgnored")
   private void mockRpcResponse(
       final Eth2Peer peer,
       final List<BlobIdentifier> blobIdentifiers,
-      List<BlobSidecar> blobSidecars) {
+      final List<BlobSidecar> blobSidecars) {
     when(peer.requestBlobSidecarsByRoot(eq(blobIdentifiers), any()))
         .thenAnswer(
             invocationOnMock -> {