diff --git a/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/graphql/reactive/GraphQlWebFluxAutoConfigurationTests.java b/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/graphql/reactive/GraphQlWebFluxAutoConfigurationTests.java
index 64aadfe805..c3bf38b154 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/graphql/reactive/GraphQlWebFluxAutoConfigurationTests.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/graphql/reactive/GraphQlWebFluxAutoConfigurationTests.java
@@ -174,7 +174,7 @@ class GraphQlWebFluxAutoConfigurationTests {
 		@Bean
 		WebInterceptor customWebInterceptor() {
 			return (webInput, interceptorChain) -> interceptorChain.next(webInput)
-					.map((output) -> output.transform((builder) -> builder.responseHeader("X-Custom-Header", "42")));
+					.doOnNext((output) -> output.getResponseHeaders().add("X-Custom-Header", "42"));
 		}
 
 	}
diff --git a/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/graphql/servlet/GraphQlWebMvcAutoConfigurationTests.java b/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/graphql/servlet/GraphQlWebMvcAutoConfigurationTests.java
index 3e1f57a16a..21b0939cf2 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/graphql/servlet/GraphQlWebMvcAutoConfigurationTests.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/graphql/servlet/GraphQlWebMvcAutoConfigurationTests.java
@@ -185,7 +185,7 @@ class GraphQlWebMvcAutoConfigurationTests {
 		@Bean
 		WebInterceptor customWebInterceptor() {
 			return (webInput, interceptorChain) -> interceptorChain.next(webInput)
-					.map((output) -> output.transform((builder) -> builder.responseHeader("X-Custom-Header", "42")));
+					.doOnNext((output) -> output.getResponseHeaders().add("X-Custom-Header", "42"));
 		}
 
 	}