diff --git a/java-spanner/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcStreamIterator.java b/java-spanner/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcStreamIterator.java
index 7b0cb08b5c84..312e841a188c 100644
--- a/java-spanner/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcStreamIterator.java
+++ b/java-spanner/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcStreamIterator.java
@@ -86,7 +86,7 @@ public String toString() {
   private boolean callCleared;
   private boolean closed;
   @Nullable private String closeMessage;
-  private final boolean withBeginTransaction;
+  private volatile boolean withBeginTransaction;
   private final boolean lastStatement;
   @Nullable private volatile Timeout streamWaitTimeout;
   @Nullable private volatile SpannerException error;
@@ -156,6 +156,14 @@ void registerListener(AsyncResultSet.StreamMessageListener streamMessageListener
     }
   }
 
+  @VisibleForTesting
+  void setCall(SpannerRpc.StreamingCall call, boolean withBeginTransaction) {
+    synchronized (this) {
+      this.withBeginTransaction = withBeginTransaction;
+    }
+    setCall(call);
+  }
+
   void setCall(SpannerRpc.StreamingCall call) {
     Timeout timeout = extractTimeout(call);
     boolean shouldCancel;