diff --git a/indexing-service/src/main/java/io/druid/indexing/overlord/ForkingTaskRunner.java b/indexing-service/src/main/java/io/druid/indexing/overlord/ForkingTaskRunner.java
index 32d421289e6..aff87140dd1 100644
--- a/indexing-service/src/main/java/io/druid/indexing/overlord/ForkingTaskRunner.java
+++ b/indexing-service/src/main/java/io/druid/indexing/overlord/ForkingTaskRunner.java
@@ -425,6 +425,7 @@ public class ForkingTaskRunner implements TaskRunner, TaskLogStreamer
                               }
                             }
 
+                            portFinder.markPortUnused(childPort);
                             if (childChatHandlerPort > 0) {
                               portFinder.markPortUnused(childChatHandlerPort);
                             }