diff --git a/interop-testing/src/main/java/io/grpc/testing/integration/StressTestClient.java b/interop-testing/src/main/java/io/grpc/testing/integration/StressTestClient.java
index c344f09e19..7fafe43be0 100644
--- a/interop-testing/src/main/java/io/grpc/testing/integration/StressTestClient.java
+++ b/interop-testing/src/main/java/io/grpc/testing/integration/StressTestClient.java
@@ -308,7 +308,9 @@ public class StressTestClient {
     }
 
     try {
-      metricsServer.shutdownNow();
+      if (metricsServer != null) {
+        metricsServer.shutdownNow();
+      }
     } catch (Throwable t) {
       log.log(Level.WARNING, "Error shutting down metrics service!", t);
     }