diff --git a/xds/src/main/java/io/grpc/xds/ClusterImplLoadBalancer.java b/xds/src/main/java/io/grpc/xds/ClusterImplLoadBalancer.java
index 0ea2c7dd75f..3b30b8fa036 100644
--- a/xds/src/main/java/io/grpc/xds/ClusterImplLoadBalancer.java
+++ b/xds/src/main/java/io/grpc/xds/ClusterImplLoadBalancer.java
@@ -236,7 +236,8 @@ public void start(SubchannelStateListener listener) {
           delegate().start(new SubchannelStateListener() {
             @Override
             public void onSubchannelState(ConnectivityStateInfo newState) {
-              if (newState.getState().equals(ConnectivityState.READY)) {
+              // Do nothing if LB has been shutdown
+              if (xdsClient != null && newState.getState().equals(ConnectivityState.READY)) {
                 // Get locality based on the connected address attributes
                 ClusterLocality updatedClusterLocality = createClusterLocalityFromAttributes(
                     subchannel.getConnectedAddressAttributes());