diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AsyncResultSetImpl.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AsyncResultSetImpl.java
index 22e57d1400..d980c90f78 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AsyncResultSetImpl.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AsyncResultSetImpl.java
@@ -498,10 +498,12 @@ public ApiFuture<Void> setCallback(Executor exec, ReadyCallback cb) {
   }
 
   private void initiateProduceRows() {
-    if (this.state == State.STREAMING_INITIALIZED) {
-      this.state = State.RUNNING;
+    synchronized (monitor) {
+      if (this.state == State.STREAMING_INITIALIZED) {
+        this.state = State.RUNNING;
+      }
+      produceRowsInitiated = true;
     }
-    produceRowsInitiated = true;
     this.service.execute(new ProduceRowsRunnable());
   }