diff --git a/server/src/main/java/org/elasticsearch/index/shard/IndexShard.java b/server/src/main/java/org/elasticsearch/index/shard/IndexShard.java
index a18c49bb99321..5b9a06a0b3b68 100644
--- a/server/src/main/java/org/elasticsearch/index/shard/IndexShard.java
+++ b/server/src/main/java/org/elasticsearch/index/shard/IndexShard.java
@@ -1335,11 +1335,12 @@ public RefreshStats refreshStats() {
     }
 
     public FlushStats flushStats() {
+        final Engine engine = getEngineOrNull();
         return new FlushStats(
             flushMetric.count(),
             periodicFlushMetric.count(),
             TimeUnit.NANOSECONDS.toMillis(flushMetric.sum()),
-            getEngineOrNull() != null ? getEngineOrNull().getTotalFlushTimeExcludingWaitingOnLockInMillis() : 0L
+            engine != null ? engine.getTotalFlushTimeExcludingWaitingOnLockInMillis() : 0L
         );
     }