diff --git a/module/spring-boot-security-oauth2-resource-server/src/main/java/org/springframework/boot/security/oauth2/server/resource/autoconfigure/reactive/ReactiveOpaqueTokenIntrospectionClientConfiguration.java b/module/spring-boot-security-oauth2-resource-server/src/main/java/org/springframework/boot/security/oauth2/server/resource/autoconfigure/reactive/ReactiveOpaqueTokenIntrospectionClientConfiguration.java
index 0cbf30ee2d49..1f1b4e86a3ba 100644
--- a/module/spring-boot-security-oauth2-resource-server/src/main/java/org/springframework/boot/security/oauth2/server/resource/autoconfigure/reactive/ReactiveOpaqueTokenIntrospectionClientConfiguration.java
+++ b/module/spring-boot-security-oauth2-resource-server/src/main/java/org/springframework/boot/security/oauth2/server/resource/autoconfigure/reactive/ReactiveOpaqueTokenIntrospectionClientConfiguration.java
@@ -17,6 +17,7 @@
 package org.springframework.boot.security.oauth2.server.resource.autoconfigure.reactive;
 
 import org.springframework.beans.factory.ObjectProvider;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.boot.security.oauth2.server.resource.autoconfigure.OAuth2ResourceServerProperties;
@@ -25,6 +26,7 @@
 import org.springframework.security.oauth2.server.resource.introspection.ReactiveOpaqueTokenIntrospector;
 import org.springframework.security.oauth2.server.resource.introspection.SpringReactiveOpaqueTokenIntrospector;
 import org.springframework.util.Assert;
+import org.springframework.web.reactive.function.client.WebClient;
 
 /**
  * Configures an {@link ReactiveOpaqueTokenIntrospector} when a token introspection
@@ -34,6 +36,7 @@
  */
 @Configuration(proxyBeanMethods = false)
 @ConditionalOnMissingBean(ReactiveOpaqueTokenIntrospector.class)
+@ConditionalOnClass(WebClient.class)
 class ReactiveOpaqueTokenIntrospectionClientConfiguration {
 
 	@Bean
diff --git a/module/spring-boot-security-oauth2-resource-server/src/test/java/org/springframework/boot/security/oauth2/server/resource/autoconfigure/reactive/ReactiveOAuth2ResourceServerAutoConfigurationTests.java b/module/spring-boot-security-oauth2-resource-server/src/test/java/org/springframework/boot/security/oauth2/server/resource/autoconfigure/reactive/ReactiveOAuth2ResourceServerAutoConfigurationTests.java
index a4206c8da860..a0d5afaaebda 100644
--- a/module/spring-boot-security-oauth2-resource-server/src/test/java/org/springframework/boot/security/oauth2/server/resource/autoconfigure/reactive/ReactiveOAuth2ResourceServerAutoConfigurationTests.java
+++ b/module/spring-boot-security-oauth2-resource-server/src/test/java/org/springframework/boot/security/oauth2/server/resource/autoconfigure/reactive/ReactiveOAuth2ResourceServerAutoConfigurationTests.java
@@ -53,6 +53,7 @@
 import org.springframework.boot.test.context.FilteredClassLoader;
 import org.springframework.boot.test.context.assertj.AssertableReactiveWebApplicationContext;
 import org.springframework.boot.test.context.runner.ReactiveWebApplicationContextRunner;
+import org.springframework.boot.testsupport.classpath.ClassPathExclusions;
 import org.springframework.boot.testsupport.classpath.resources.WithResource;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -431,6 +432,18 @@ void autoConfigurationWhenIntrospectionUriAvailableShouldConfigureIntrospectionC
 			});
 	}
 
+	@Test
+	@ClassPathExclusions("spring-webflux-*.jar")
+	void withoutWebFluxWhenIntrospectionUriIsAvailableNoTokenIntrospectorIsConfigured() {
+		new ReactiveWebApplicationContextRunner()
+			.withConfiguration(AutoConfigurations.of(ReactiveOAuth2ResourceServerAutoConfiguration.class))
+			.withPropertyValues(
+					"spring.security.oauth2.resourceserver.opaquetoken.introspection-uri=https://check-token.com",
+					"spring.security.oauth2.resourceserver.opaquetoken.client-id=my-client-id",
+					"spring.security.oauth2.resourceserver.opaquetoken.client-secret=my-client-secret")
+			.run((context) -> assertThat(context).doesNotHaveBean(ReactiveOpaqueTokenIntrospector.class));
+	}
+
 	private void assertSpringReactiveOpaqueTokenIntrospectorBuilderCustomization(
 			AssertableReactiveWebApplicationContext context) {
 		SpringReactiveOpaqueTokenIntrospectorBuilderCustomizer customizer = context.getBean(