diff --git a/solr/core/src/test/org/apache/solr/handler/component/DistributedDebugComponentTest.java b/solr/core/src/test/org/apache/solr/handler/component/DistributedDebugComponentTest.java
index 06df11be9a0..62cdfd41249 100644
--- a/solr/core/src/test/org/apache/solr/handler/component/DistributedDebugComponentTest.java
+++ b/solr/core/src/test/org/apache/solr/handler/component/DistributedDebugComponentTest.java
@@ -72,6 +72,8 @@ public class DistributedDebugComponentTest extends SolrJettyTestBase {
   public static void afterTest() throws Exception {
     collection1.shutdown();
     collection2.shutdown();
+    collection1 = null;
+    collection2 = null;
     jetty.stop();
     jetty=null;
     cleanUpJettyHome(solrHome);