diff --git a/spring-test/src/main/java/org/springframework/test/web/reactive/server/DefaultWebTestClientBuilder.java b/spring-test/src/main/java/org/springframework/test/web/reactive/server/DefaultWebTestClientBuilder.java
index 5d07813ddf..41d007da75 100644
--- a/spring-test/src/main/java/org/springframework/test/web/reactive/server/DefaultWebTestClientBuilder.java
+++ b/spring-test/src/main/java/org/springframework/test/web/reactive/server/DefaultWebTestClientBuilder.java
@@ -146,7 +146,7 @@ class DefaultWebTestClientBuilder implements WebTestClient.Builder {
 				new HttpHandlerConnector(this.httpHandlerBuilder.build()));
 
 		DefaultWebTestClientBuilder webTestClientBuilder = new DefaultWebTestClientBuilder(
-				this.webClientBuilder.build().mutate(), this.httpHandlerBuilder,
+				this.webClientBuilder.cloneBuilder(), this.httpHandlerBuilder,
 				this.connector, this.responseTimeout);
 
 		return new DefaultWebTestClient(this.webClientBuilder,