diff --git a/core/src/test/java/org/elasticsearch/action/admin/indices/segments/IndicesSegmentsRequestTests.java b/core/src/test/java/org/elasticsearch/action/admin/indices/segments/IndicesSegmentsRequestTests.java
index 011ce815a01..291c7bc5c19 100644
--- a/core/src/test/java/org/elasticsearch/action/admin/indices/segments/IndicesSegmentsRequestTests.java
+++ b/core/src/test/java/org/elasticsearch/action/admin/indices/segments/IndicesSegmentsRequestTests.java
@@ -45,19 +45,19 @@ public class IndicesSegmentsRequestTests extends ESSingleNodeTestCase {
             String id = Integer.toString(j);
             client().prepareIndex("test", "type1", id).setSource("text", "sometext").get();
         }
-        client().admin().indices().prepareFlush("test").get();
+        client().admin().indices().prepareFlush("test").setWaitIfOngoing(true).get();
     }
 
     public void testBasic() {
         IndicesSegmentResponse rsp = client().admin().indices().prepareSegments("test").get();
         List<Segment> segments = rsp.getIndices().get("test").iterator().next().getShards()[0].getSegments();
-        assertNull(segments.get(0).ramTree);
+        assertNull(segments.get(0).toString(), segments.get(0).ramTree);
     }
 
     public void testVerbose() {
         IndicesSegmentResponse rsp = client().admin().indices().prepareSegments("test").setVerbose(true).get();
         List<Segment> segments = rsp.getIndices().get("test").iterator().next().getShards()[0].getSegments();
-        assertNotNull(segments.get(0).ramTree);
+        assertNotNull(segments.get(0).toString(), segments.get(0).ramTree);
     }
 
     /**