diff --git a/ethereum/statetransition/src/main/java/tech/pegasys/teku/statetransition/util/BlockBlobSidecarsTrackersPoolImpl.java b/ethereum/statetransition/src/main/java/tech/pegasys/teku/statetransition/util/BlockBlobSidecarsTrackersPoolImpl.java
index d305fb55fa8..b63d8894097 100644
--- a/ethereum/statetransition/src/main/java/tech/pegasys/teku/statetransition/util/BlockBlobSidecarsTrackersPoolImpl.java
+++ b/ethereum/statetransition/src/main/java/tech/pegasys/teku/statetransition/util/BlockBlobSidecarsTrackersPoolImpl.java
@@ -407,7 +407,8 @@ public synchronized boolean containsBlobSidecar(final BlobIdentifier blobIdentif
   }
 
   @Override
-  public Optional<BlobSidecar> getBlobSidecar(final Bytes32 blockRoot, final UInt64 index) {
+  public synchronized Optional<BlobSidecar> getBlobSidecar(
+      final Bytes32 blockRoot, final UInt64 index) {
     return Optional.ofNullable(blockBlobSidecarsTrackers.get(blockRoot))
         .flatMap(tracker -> tracker.getBlobSidecar(index));
   }