diff --git a/spring-messaging/src/main/java/org/springframework/messaging/handler/invocation/reactive/AbstractEncoderMethodReturnValueHandler.java b/spring-messaging/src/main/java/org/springframework/messaging/handler/invocation/reactive/AbstractEncoderMethodReturnValueHandler.java
index c2df6f86dc..0981f408c4 100644
--- a/spring-messaging/src/main/java/org/springframework/messaging/handler/invocation/reactive/AbstractEncoderMethodReturnValueHandler.java
+++ b/spring-messaging/src/main/java/org/springframework/messaging/handler/invocation/reactive/AbstractEncoderMethodReturnValueHandler.java
@@ -16,13 +16,10 @@
 
 package org.springframework.messaging.handler.invocation.reactive;
 
-import java.lang.reflect.Method;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 
-import kotlin.reflect.KFunction;
-import kotlin.reflect.jvm.ReflectJvmMapping;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.reactivestreams.Publisher;
@@ -135,9 +132,7 @@ public abstract class AbstractEncoderMethodReturnValueHandler implements Handler
 		ResolvableType elementType;
 		if (adapter != null) {
 			publisher = adapter.toPublisher(content);
-			boolean isUnwrapped = KotlinDetector.isKotlinReflectPresent() &&
-					KotlinDetector.isKotlinType(returnType.getContainingClass()) &&
-					KotlinDelegate.isSuspend(returnType.getMethod()) &&
+			boolean isUnwrapped = KotlinDetector.isSuspendingFunction(returnType.getMethod()) &&
 					!COROUTINES_FLOW_CLASS_NAME.equals(returnValueType.toClass().getName());
 			ResolvableType genericType = isUnwrapped ? returnValueType : returnValueType.getGeneric();
 			elementType = getElementType(adapter, genericType);
@@ -218,19 +213,4 @@ public abstract class AbstractEncoderMethodReturnValueHandler implements Handler
 	 */
 	protected abstract Mono<Void> handleNoContent(MethodParameter returnType, Message<?> message);
 
-
-	/**
-	 * Inner class to avoid a hard dependency on Kotlin at runtime.
-	 */
-	private static class KotlinDelegate {
-
-		private static boolean isSuspend(@Nullable Method method) {
-			if (method == null) {
-				return false;
-			}
-			KFunction<?> function = ReflectJvmMapping.getKotlinFunction(method);
-			return (function != null && function.isSuspend());
-		}
-	}
-
 }
diff --git a/spring-webflux/src/main/java/org/springframework/web/reactive/result/method/annotation/AbstractMessageWriterResultHandler.java b/spring-webflux/src/main/java/org/springframework/web/reactive/result/method/annotation/AbstractMessageWriterResultHandler.java
index a4b29e3e69..40652318fb 100644
--- a/spring-webflux/src/main/java/org/springframework/web/reactive/result/method/annotation/AbstractMessageWriterResultHandler.java
+++ b/spring-webflux/src/main/java/org/springframework/web/reactive/result/method/annotation/AbstractMessageWriterResultHandler.java
@@ -16,13 +16,10 @@
 
 package org.springframework.web.reactive.result.method.annotation;
 
-import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Set;
 
-import kotlin.reflect.KFunction;
-import kotlin.reflect.jvm.ReflectJvmMapping;
 import org.reactivestreams.Publisher;
 import reactor.core.publisher.Mono;
 
@@ -131,9 +128,7 @@ public abstract class AbstractMessageWriterResultHandler extends HandlerResultHa
 		ResolvableType actualElementType;
 		if (adapter != null) {
 			publisher = adapter.toPublisher(body);
-			boolean isUnwrapped = KotlinDetector.isKotlinReflectPresent() &&
-					KotlinDetector.isKotlinType(bodyParameter.getContainingClass()) &&
-					KotlinDelegate.isSuspend(bodyParameter.getMethod()) &&
+			boolean isUnwrapped = KotlinDetector.isSuspendingFunction(bodyParameter.getMethod()) &&
 					!COROUTINES_FLOW_CLASS_NAME.equals(bodyType.toClass().getName());
 			ResolvableType genericType = isUnwrapped ? bodyType : bodyType.getGeneric();
 			elementType = getElementType(adapter, genericType);
@@ -203,16 +198,4 @@ public abstract class AbstractMessageWriterResultHandler extends HandlerResultHa
 		return writableMediaTypes;
 	}
 
-
-	/**
-	 * Inner class to avoid a hard dependency on Kotlin at runtime.
-	 */
-	private static class KotlinDelegate {
-
-		private static boolean isSuspend(Method method) {
-			KFunction<?> function = ReflectJvmMapping.getKotlinFunction(method);
-			return function != null && function.isSuspend();
-		}
-	}
-
 }