diff --git a/transport/src/main/java/io/netty/channel/socket/nio/NioWorker.java b/transport/src/main/java/io/netty/channel/socket/nio/NioWorker.java
index a6b31cc45e..6b5047064c 100644
--- a/transport/src/main/java/io/netty/channel/socket/nio/NioWorker.java
+++ b/transport/src/main/java/io/netty/channel/socket/nio/NioWorker.java
@@ -136,7 +136,9 @@ public class NioWorker extends AbstractNioWorker {
                 setInterestOps(channel, future, channel.getRawInterestOps());
             }
             if (future != null) {
-                ((NioSocketChannel) channel).setConnected();
+                if (channel instanceof NioSocketChannel) {
+                    ((NioSocketChannel) channel).setConnected();
+                }
                 future.setSuccess();
             }