diff --git a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/FunctionAroundWrapper.java b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/FunctionAroundWrapper.java
index 864075dce..263dfa0d6 100644
--- a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/FunctionAroundWrapper.java
+++ b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/FunctionAroundWrapper.java
@@ -43,15 +43,8 @@ public abstract class FunctionAroundWrapper {
 		String functionalTracingEnabledStr = System.getProperty("spring.cloud.function.observability.enabled");
 		boolean functionalTracingEnabled = StringUtils.hasText(functionalTracingEnabledStr)
 				? Boolean.parseBoolean(functionalTracingEnabledStr) : true;
-		if (functionalTracingEnabled && !(input instanceof Publisher) && input instanceof Message) {
-			boolean isSkipOutputConversion = targetFunction.isSkipOutputConversion();
-			targetFunction.setSkipOutputConversion(true);
-			try {
-				return this.doApply(input, targetFunction);
-			}
-			finally {
-				targetFunction.setSkipOutputConversion(isSkipOutputConversion);
-			}
+		if (functionalTracingEnabled && !(input instanceof Publisher) && input instanceof Message && !FunctionTypeUtils.isCollectionOfMessage(targetFunction.getOutputType())) {
+			return this.doApply(input, targetFunction);
 		}
 		else {
 			return targetFunction.apply(input);
diff --git a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/FunctionTypeUtils.java b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/FunctionTypeUtils.java
index 919c67801..cd4724185 100644
--- a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/FunctionTypeUtils.java
+++ b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/FunctionTypeUtils.java
@@ -99,6 +99,7 @@ public final class FunctionTypeUtils {
 			return true;
 		}
 		type = getGenericType(type);
+		type = type == null ? Object.class : type;
 		Class<?> rawType = type instanceof ParameterizedType ? getRawType(type) : (Class<?>) type;
 		return Collection.class.isAssignableFrom(rawType) || JsonNode.class.isAssignableFrom(rawType);
 	}
diff --git a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/SimpleFunctionRegistry.java b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/SimpleFunctionRegistry.java
index 3943831a1..3c91633ab 100644
--- a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/SimpleFunctionRegistry.java
+++ b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/SimpleFunctionRegistry.java
@@ -224,10 +224,6 @@ public class SimpleFunctionRegistry implements FunctionRegistry {
 			logger.debug("Function '" + functionDefinition + "' is not found in cache");
 		}
 
-		if (function != null) {
-			function = this.wrapInAroundAdviceIfNecessary(function);
-		}
-
 		return (T) function;
 	}
 
@@ -258,28 +254,6 @@ public class SimpleFunctionRegistry implements FunctionRegistry {
 		return functionDefinition;
 	}
 
-	/**
-	 * This is primarily to support spring-cloud-sleauth.
-	 * There is no current use cases in functions where it is used.
-	 * The approach may change in the future.
-	 */
-	private FunctionInvocationWrapper wrapInAroundAdviceIfNecessary(FunctionInvocationWrapper function) {
-		FunctionInvocationWrapper wrappedFunction = function;
-		if (function != null && this.functionAroundWrapper != null) {
-			wrappedFunction = new FunctionInvocationWrapper(function) {
-				@Override
-				Object doApply(Object input) {
-					if (logger.isDebugEnabled()) {
-						logger.debug("Executing around advise(s): " + functionAroundWrapper);
-					}
-
-					return functionAroundWrapper.apply(input, function);
-				}
-			};
-		}
-		return wrappedFunction;
-	}
-
 	/*
 	 *
 	 */
@@ -429,6 +403,8 @@ public class SimpleFunctionRegistry implements FunctionRegistry {
 
 		private boolean propagateInputHeaders;
 
+		private boolean wrapped;
+
 		/*
 		 * This is primarily to support Stream's ability to access
 		 * un-converted payload (e.g., to evaluate expression on some attribute of a payload)
@@ -437,20 +413,6 @@ public class SimpleFunctionRegistry implements FunctionRegistry {
 		 */
 		private Function<Object, Object> enhancer;
 
-		FunctionInvocationWrapper(FunctionInvocationWrapper function) {
-			this.expectedOutputContentType = function.expectedOutputContentType;
-			this.skipOutputConversion = function.skipOutputConversion;
-			this.skipInputConversion = function.skipInputConversion;
-			this.target = function.target;
-			this.propagateInputHeaders = function.propagateInputHeaders;
-			this.composed = function.composed;
-			this.inputType = function.inputType;
-			this.composed = function.composed;
-			this.outputType = function.outputType;
-			this.functionDefinition = function.functionDefinition;
-			this.message = this.inputType != null && FunctionTypeUtils.isMessage(this.inputType);
-		}
-
 		FunctionInvocationWrapper(String functionDefinition,  Object target, Type inputType, Type outputType) {
 			this.target = target;
 			this.inputType = this.normalizeType(inputType);
@@ -559,12 +521,14 @@ public class SimpleFunctionRegistry implements FunctionRegistry {
 			if (logger.isDebugEnabled() && !(input  instanceof Publisher)) {
 				logger.debug("Invoking function " + this);
 			}
-			//Object result = (this.getTarget() instanceof PassThruFunction) ? input : this.doApply(input);
 
-			Object result = this.doApply(input);
-
-			if (result != null && this.outputType != null) {
-				result = this.convertOutputIfNecessary(result, this.outputType, this.expectedOutputContentType);
+			Object result;
+			if (functionAroundWrapper != null && !this.wrapped) {
+				this.wrapped = true;
+				result = functionAroundWrapper.apply(input, this);
+			}
+			else {
+				result = this.doApply(input);
 			}
 
 			return result;
@@ -720,6 +684,10 @@ public class SimpleFunctionRegistry implements FunctionRegistry {
 			else { // Function
 				result = this.invokeFunction(convertedInput);
 			}
+
+			if (result != null && this.outputType != null) {
+				result = this.convertOutputIfNecessary(result, this.outputType, this.expectedOutputContentType);
+			}
 			return result;
 		}
 
diff --git a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/observability/ObservationFunctionAroundWrapper.java b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/observability/ObservationFunctionAroundWrapper.java
index c07b93439..810aaa0ee 100644
--- a/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/observability/ObservationFunctionAroundWrapper.java
+++ b/spring-cloud-function-context/src/main/java/org/springframework/cloud/function/observability/ObservationFunctionAroundWrapper.java
@@ -20,7 +20,6 @@ import io.micrometer.observation.Observation;
 import io.micrometer.observation.ObservationRegistry;
 
 import org.springframework.cloud.function.context.catalog.FunctionAroundWrapper;
-import org.springframework.cloud.function.context.catalog.FunctionTypeUtils;
 import org.springframework.cloud.function.context.catalog.SimpleFunctionRegistry;
 import org.springframework.lang.Nullable;
 import org.springframework.messaging.Message;
@@ -43,18 +42,15 @@ public class ObservationFunctionAroundWrapper extends FunctionAroundWrapper {
 
 	@Override
 	protected Object doApply(Object message, SimpleFunctionRegistry.FunctionInvocationWrapper targetFunction) {
-		if (FunctionTypeUtils.isCollectionOfMessage(targetFunction.getOutputType())) {
-			return targetFunction.apply(message); // no instrumentation
-		}
 		return nonReactorStream((Message<?>) message, targetFunction);
 	}
 
 	private Object nonReactorStream(Message<?> message,
 		SimpleFunctionRegistry.FunctionInvocationWrapper targetFunction) {
-		if (targetFunction.isConsumer() || targetFunction.isFunction()) {
+		//if (targetFunction.isConsumer() || targetFunction.isFunction()) {
 			return functionProcessingObservation(targetFunction, message).observe(() -> targetFunction.apply(message));
-		}
-		return functionProcessingObservation(targetFunction, message).observe(targetFunction::get);
+//		}
+//		return functionProcessingObservation(targetFunction, message).observe(targetFunction::get);
 	}
 
 	private Observation functionProcessingObservation(SimpleFunctionRegistry.FunctionInvocationWrapper targetFunction, Message<?> message) {