diff --git a/spring-test/src/main/java/org/springframework/test/web/reactive/server/AbstractMockServerSpec.java b/spring-test/src/main/java/org/springframework/test/web/reactive/server/AbstractMockServerSpec.java
index e2084f7a21d..5291a0c7685 100644
--- a/spring-test/src/main/java/org/springframework/test/web/reactive/server/AbstractMockServerSpec.java
+++ b/spring-test/src/main/java/org/springframework/test/web/reactive/server/AbstractMockServerSpec.java
@@ -35,19 +35,19 @@ import org.springframework.web.server.adapter.WebHttpHandlerBuilder;
 abstract class AbstractMockServerSpec<B extends WebTestClient.MockServerSpec<B>>
 		implements WebTestClient.MockServerSpec<B> {
 
-	private final ExchangeMutatorWebFilter exchangeMutatorFilter = new ExchangeMutatorWebFilter();
+	private final ExchangeMutatingWebFilter exchangeMutatingWebFilter = new ExchangeMutatingWebFilter();
 
 	private final List<WebFilter> filters = new ArrayList<>(4);
 
 
 	AbstractMockServerSpec() {
-		this.filters.add(this.exchangeMutatorFilter);
+		this.filters.add(this.exchangeMutatingWebFilter);
 	}
 
 
 	@Override
 	public <T extends B> T exchangeMutator(UnaryOperator<ServerWebExchange> mutator) {
-		this.exchangeMutatorFilter.register(mutator);
+		this.exchangeMutatingWebFilter.registerGlobalMutator(mutator);
 		return self();
 	}
 
@@ -67,7 +67,7 @@ abstract class AbstractMockServerSpec<B extends WebTestClient.MockServerSpec<B>>
 	public WebTestClient.Builder configureClient() {
 		WebHttpHandlerBuilder builder = initHttpHandlerBuilder();
 		filtersInReverse().forEach(builder::prependFilter);
-		return new DefaultWebTestClientBuilder(builder.build(), this.exchangeMutatorFilter);
+		return new DefaultWebTestClientBuilder(builder.build(), this.exchangeMutatingWebFilter);
 	}
 
 	/**
diff --git a/spring-test/src/main/java/org/springframework/test/web/reactive/server/DefaultWebTestClient.java b/spring-test/src/main/java/org/springframework/test/web/reactive/server/DefaultWebTestClient.java
index 4dfca1dbb54..9c825241169 100644
--- a/spring-test/src/main/java/org/springframework/test/web/reactive/server/DefaultWebTestClient.java
+++ b/spring-test/src/main/java/org/springframework/test/web/reactive/server/DefaultWebTestClient.java
@@ -69,7 +69,7 @@ class DefaultWebTestClient implements WebTestClient {
 
 	private final WiretapConnector wiretapConnector;
 
-	private final ExchangeMutatorWebFilter exchangeMutatorWebFilter;
+	private final ExchangeMutatingWebFilter exchangeMutatingWebFilter;
 
 	private final Duration timeout;
 
@@ -77,20 +77,20 @@ class DefaultWebTestClient implements WebTestClient {
 
 
 	DefaultWebTestClient(WebClient.Builder webClientBuilder, ClientHttpConnector connector,
-			ExchangeMutatorWebFilter webFilter, Duration timeout) {
+			ExchangeMutatingWebFilter exchangeMutatingWebFilter, Duration timeout) {
 
 		Assert.notNull(webClientBuilder, "WebClient.Builder is required");
 
 		this.wiretapConnector = new WiretapConnector(connector);
 		this.webClient = webClientBuilder.clientConnector(this.wiretapConnector).build();
-		this.exchangeMutatorWebFilter = webFilter;
+		this.exchangeMutatingWebFilter = exchangeMutatingWebFilter;
 		this.timeout = (timeout != null ? timeout : Duration.ofSeconds(5));
 	}
 
 	private DefaultWebTestClient(DefaultWebTestClient webTestClient, ExchangeFilterFunction filter) {
 		this.webClient = webTestClient.webClient.filter(filter);
 		this.wiretapConnector = webTestClient.wiretapConnector;
-		this.exchangeMutatorWebFilter = webTestClient.exchangeMutatorWebFilter;
+		this.exchangeMutatingWebFilter = webTestClient.exchangeMutatingWebFilter;
 		this.timeout = webTestClient.timeout;
 	}
 
@@ -150,13 +150,13 @@ class DefaultWebTestClient implements WebTestClient {
 	@Override
 	public WebTestClient exchangeMutator(UnaryOperator<ServerWebExchange> mutator) {
 
-		Assert.notNull(this.exchangeMutatorWebFilter,
+		Assert.notNull(this.exchangeMutatingWebFilter,
 				"This option is applicable only for tests without an actual running server");
 
 		return filter((request, next) -> {
 			String requestId = request.headers().getFirst(WiretapConnector.REQUEST_ID_HEADER_NAME);
 			Assert.notNull(requestId, "No request-id header");
-			this.exchangeMutatorWebFilter.register(requestId, mutator);
+			this.exchangeMutatingWebFilter.registerPerRequestMutator(requestId, mutator);
 			return next.exchange(request);
 		});
 	}
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 e7320d6aa3e..019ebf1ad48 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
@@ -37,7 +37,7 @@ class DefaultWebTestClientBuilder implements WebTestClient.Builder {
 
 	private final ClientHttpConnector connector;
 
-	private final ExchangeMutatorWebFilter exchangeMutatorFilter;
+	private final ExchangeMutatingWebFilter exchangeMutatingWebFilter;
 
 	private Duration responseTimeout;
 
@@ -48,12 +48,12 @@ class DefaultWebTestClientBuilder implements WebTestClient.Builder {
 
 	DefaultWebTestClientBuilder(ClientHttpConnector connector) {
 		this.connector = connector;
-		this.exchangeMutatorFilter = null;
+		this.exchangeMutatingWebFilter = null;
 	}
 
-	DefaultWebTestClientBuilder(HttpHandler httpHandler, ExchangeMutatorWebFilter exchangeMutatorFilter) {
+	DefaultWebTestClientBuilder(HttpHandler httpHandler, ExchangeMutatingWebFilter exchangeMutatingWebFilter) {
 		this.connector = new HttpHandlerConnector(httpHandler);
-		this.exchangeMutatorFilter = exchangeMutatorFilter;
+		this.exchangeMutatingWebFilter = exchangeMutatingWebFilter;
 	}
 
 
@@ -96,7 +96,7 @@ class DefaultWebTestClientBuilder implements WebTestClient.Builder {
 	@Override
 	public WebTestClient build() {
 		return new DefaultWebTestClient(this.webClientBuilder, this.connector,
-				this.exchangeMutatorFilter, this.responseTimeout);
+				this.exchangeMutatingWebFilter, this.responseTimeout);
 	}
 
 }
diff --git a/spring-test/src/main/java/org/springframework/test/web/reactive/server/ExchangeMutatorWebFilter.java b/spring-test/src/main/java/org/springframework/test/web/reactive/server/ExchangeMutatingWebFilter.java
similarity index 70%
rename from spring-test/src/main/java/org/springframework/test/web/reactive/server/ExchangeMutatorWebFilter.java
rename to spring-test/src/main/java/org/springframework/test/web/reactive/server/ExchangeMutatingWebFilter.java
index 709fa741364..87395d1f6ea 100644
--- a/spring-test/src/main/java/org/springframework/test/web/reactive/server/ExchangeMutatorWebFilter.java
+++ b/spring-test/src/main/java/org/springframework/test/web/reactive/server/ExchangeMutatingWebFilter.java
@@ -29,15 +29,18 @@ import org.springframework.web.server.WebFilter;
 import org.springframework.web.server.WebFilterChain;
 
 /**
- * WebFilter that applies global and request-specific transformation on
+ * WebFilter for applying global and per-request transformations to a
  * {@link ServerWebExchange}.
  *
  * @author Rossen Stoyanchev
  * @since 5.0
  */
-class ExchangeMutatorWebFilter implements WebFilter {
+class ExchangeMutatingWebFilter implements WebFilter {
 
-	private volatile Function<ServerWebExchange, ServerWebExchange> globalMutator;
+	private static final Function<ServerWebExchange, ServerWebExchange> NO_OP_MUTATOR = e -> e;
+
+
+	private volatile Function<ServerWebExchange, ServerWebExchange> globalMutator = NO_OP_MUTATOR;
 
 	private final Map<String, Function<ServerWebExchange, ServerWebExchange>> perRequestMutators =
 			new ConcurrentHashMap<>(4);
@@ -47,9 +50,9 @@ class ExchangeMutatorWebFilter implements WebFilter {
 	 * Register a global transformation function to apply to all requests.
 	 * @param mutator the transformation function
 	 */
-	public void register(UnaryOperator<ServerWebExchange> mutator) {
+	public void registerGlobalMutator(UnaryOperator<ServerWebExchange> mutator) {
 		Assert.notNull(mutator, "'mutator' is required");
-		this.globalMutator = this.globalMutator != null ? this.globalMutator.andThen(mutator) : mutator;
+		this.globalMutator = this.globalMutator.andThen(mutator);
 	}
 
 	/**
@@ -57,7 +60,7 @@ class ExchangeMutatorWebFilter implements WebFilter {
 	 * @param requestId the "request-id" header value identifying the request
 	 * @param mutator the transformation function
 	 */
-	public void register(String requestId, UnaryOperator<ServerWebExchange> mutator) {
+	public void registerPerRequestMutator(String requestId, UnaryOperator<ServerWebExchange> mutator) {
 		this.perRequestMutators.compute(requestId,
 				(s, value) -> value != null ? value.andThen(mutator) : mutator);
 	}
@@ -65,18 +68,15 @@ class ExchangeMutatorWebFilter implements WebFilter {
 
 	@Override
 	public Mono<Void> filter(ServerWebExchange exchange, WebFilterChain chain) {
-
-		if (this.globalMutator != null) {
-			exchange = this.globalMutator.apply(exchange);
-		}
-
-		String requestId = WiretapConnector.getRequestId(exchange.getRequest().getHeaders());
-		Function<ServerWebExchange, ServerWebExchange> mutator = this.perRequestMutators.remove(requestId);
-		if (mutator != null) {
-			exchange = mutator.apply(exchange);
-		}
-
+		exchange = this.globalMutator.apply(exchange);
+		exchange = getMutatorFor(exchange).apply(exchange);
 		return chain.filter(exchange);
 	}
 
+	private Function<ServerWebExchange, ServerWebExchange> getMutatorFor(ServerWebExchange exchange) {
+		String id = WiretapConnector.getRequestId(exchange.getRequest().getHeaders());
+		Function<ServerWebExchange, ServerWebExchange> mutator = this.perRequestMutators.remove(id);
+		return mutator != null ? mutator : NO_OP_MUTATOR;
+	}
+
 }
diff --git a/spring-webflux/src/main/java/org/springframework/web/reactive/function/client/WebClient.java b/spring-webflux/src/main/java/org/springframework/web/reactive/function/client/WebClient.java
index 44ed674564a..b8e1aae32ff 100644
--- a/spring-webflux/src/main/java/org/springframework/web/reactive/function/client/WebClient.java
+++ b/spring-webflux/src/main/java/org/springframework/web/reactive/function/client/WebClient.java
@@ -375,22 +375,23 @@ public interface WebClient {
 		 * Exchange the request for a {@code ClientResponse} with full access
 		 * to the response status and headers before extracting the body.
 		 *
-		 * <p>Use {@link Mono#then(Function)} or {@link Mono#flatMap(Function)}
-		 * to compose further on the response:
+		 * <p>Use {@link Mono#flatMap(Function)} or
+		 * {@link Mono#flatMapMany(Function)} to compose further on the response:
 		 *
 		 * <pre>
 		 *	Mono&lt;Pojo&gt; mono = client.get().uri("/")
 		 *		.accept(MediaType.APPLICATION_JSON)
 		 *		.exchange()
-		 *		.then(response -> response.bodyToMono(Pojo.class));
+		 *		.flatMap(response -> response.bodyToMono(Pojo.class));
 		 *
 		 *	Flux&lt;Pojo&gt; flux = client.get().uri("/")
 		 *		.accept(MediaType.APPLICATION_STREAM_JSON)
 		 *		.exchange()
-		 *		.then(response -> response.bodyToFlux(Pojo.class));
+		 *		.flatMapMany(response -> response.bodyToFlux(Pojo.class));
 		 * </pre>
 		 *
 		 * @return a {@code Mono} with the response
+		 * @see #retrieve()
 		 */
 		Mono<ClientResponse> exchange();