diff --git a/clients/src/test/java/org/apache/kafka/clients/NetworkClientTest.java b/clients/src/test/java/org/apache/kafka/clients/NetworkClientTest.java
index d4210aeb1640..834bccaaf529 100644
--- a/clients/src/test/java/org/apache/kafka/clients/NetworkClientTest.java
+++ b/clients/src/test/java/org/apache/kafka/clients/NetworkClientTest.java
@@ -639,6 +639,8 @@ defaultRequestTimeoutMs, connectionSetupTimeoutMsTest, connectionSetupTimeoutMax
             LeastLoadedNodeAlgorithm.VANILLA, new ArrayList<>());
         nc.ready(node, time.milliseconds());
         assertFalse(client.isReady(node, time.milliseconds()));
+        assertThrows(ConfigException.class, () -> nc.leastLoadedNode(time.milliseconds()));
+
         assertEquals(null, nc.leastLoadedNode(time.milliseconds()));
     }