diff --git a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/client/reactive/ReactiveOAuth2ClientConfigurations.java b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/client/reactive/ReactiveOAuth2ClientConfigurations.java
index 8d25fbc2e3..8eb3871b93 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/client/reactive/ReactiveOAuth2ClientConfigurations.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/client/reactive/ReactiveOAuth2ClientConfigurations.java
@@ -28,7 +28,6 @@ import org.springframework.boot.autoconfigure.security.oauth2.client.OAuth2Clien
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Conditional;
 import org.springframework.context.annotation.Configuration;
-import org.springframework.security.config.annotation.web.reactive.EnableWebFluxSecurity;
 import org.springframework.security.config.web.server.ServerHttpSecurity;
 import org.springframework.security.oauth2.client.InMemoryReactiveOAuth2AuthorizedClientService;
 import org.springframework.security.oauth2.client.ReactiveOAuth2AuthorizedClientService;
@@ -38,7 +37,6 @@ import org.springframework.security.oauth2.client.registration.ReactiveClientReg
 import org.springframework.security.oauth2.client.web.server.AuthenticatedPrincipalServerOAuth2AuthorizedClientRepository;
 import org.springframework.security.oauth2.client.web.server.ServerOAuth2AuthorizedClientRepository;
 import org.springframework.security.web.server.SecurityWebFilterChain;
-import org.springframework.security.web.server.WebFilterChainProxy;
 
 import static org.springframework.security.config.Customizer.withDefaults;
 
@@ -94,13 +92,6 @@ class ReactiveOAuth2ClientConfigurations {
 				return http.build();
 			}
 
-			@Configuration(proxyBeanMethods = false)
-			@ConditionalOnMissingBean(WebFilterChainProxy.class)
-			@EnableWebFluxSecurity
-			static class EnableWebFluxSecurityConfiguration {
-
-			}
-
 		}
 
 	}
diff --git a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/resource/reactive/ReactiveOAuth2ResourceServerJwkConfiguration.java b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/resource/reactive/ReactiveOAuth2ResourceServerJwkConfiguration.java
index 31cb13aa60..5f5cba160e 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/resource/reactive/ReactiveOAuth2ResourceServerJwkConfiguration.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/resource/reactive/ReactiveOAuth2ResourceServerJwkConfiguration.java
@@ -35,7 +35,6 @@ import org.springframework.boot.autoconfigure.security.oauth2.resource.OAuth2Res
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Conditional;
 import org.springframework.context.annotation.Configuration;
-import org.springframework.security.config.annotation.web.reactive.EnableWebFluxSecurity;
 import org.springframework.security.config.web.server.ServerHttpSecurity;
 import org.springframework.security.config.web.server.ServerHttpSecurity.OAuth2ResourceServerSpec;
 import org.springframework.security.oauth2.core.DelegatingOAuth2TokenValidator;
@@ -50,7 +49,6 @@ import org.springframework.security.oauth2.jwt.NimbusReactiveJwtDecoder.JwkSetUr
 import org.springframework.security.oauth2.jwt.ReactiveJwtDecoder;
 import org.springframework.security.oauth2.jwt.SupplierReactiveJwtDecoder;
 import org.springframework.security.web.server.SecurityWebFilterChain;
-import org.springframework.security.web.server.WebFilterChainProxy;
 import org.springframework.util.CollectionUtils;
 
 /**
@@ -179,13 +177,6 @@ class ReactiveOAuth2ResourceServerJwkConfiguration {
 			server.jwt((jwt) -> jwt.jwtDecoder(decoder));
 		}
 
-		@Configuration(proxyBeanMethods = false)
-		@ConditionalOnMissingBean(WebFilterChainProxy.class)
-		@EnableWebFluxSecurity
-		static class EnableWebFluxSecurityConfiguration {
-
-		}
-
 	}
 
 }
diff --git a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/resource/reactive/ReactiveOAuth2ResourceServerOpaqueTokenConfiguration.java b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/resource/reactive/ReactiveOAuth2ResourceServerOpaqueTokenConfiguration.java
index dbeb778d87..f4d9614253 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/resource/reactive/ReactiveOAuth2ResourceServerOpaqueTokenConfiguration.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/resource/reactive/ReactiveOAuth2ResourceServerOpaqueTokenConfiguration.java
@@ -22,12 +22,10 @@ import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.boot.autoconfigure.security.oauth2.resource.OAuth2ResourceServerProperties;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
-import org.springframework.security.config.annotation.web.reactive.EnableWebFluxSecurity;
 import org.springframework.security.config.web.server.ServerHttpSecurity;
 import org.springframework.security.oauth2.server.resource.introspection.ReactiveOpaqueTokenIntrospector;
 import org.springframework.security.oauth2.server.resource.introspection.SpringReactiveOpaqueTokenIntrospector;
 import org.springframework.security.web.server.SecurityWebFilterChain;
-import org.springframework.security.web.server.WebFilterChainProxy;
 
 import static org.springframework.security.config.Customizer.withDefaults;
 
@@ -66,13 +64,6 @@ class ReactiveOAuth2ResourceServerOpaqueTokenConfiguration {
 			return http.build();
 		}
 
-		@Configuration(proxyBeanMethods = false)
-		@ConditionalOnMissingBean(WebFilterChainProxy.class)
-		@EnableWebFluxSecurity
-		static class EnableWebFluxSecurityConfiguration {
-
-		}
-
 	}
 
 }
diff --git a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/reactive/ReactiveSecurityAutoConfiguration.java b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/reactive/ReactiveSecurityAutoConfiguration.java
index 5bcb151be4..9e07d8f9b9 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/reactive/ReactiveSecurityAutoConfiguration.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/reactive/ReactiveSecurityAutoConfiguration.java
@@ -17,21 +17,21 @@
 package org.springframework.boot.autoconfigure.security.reactive;
 
 import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
 
 import org.springframework.boot.autoconfigure.AutoConfiguration;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
-import org.springframework.boot.autoconfigure.condition.AnyNestedCondition;
-import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication;
 import org.springframework.boot.autoconfigure.security.SecurityProperties;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
-import org.springframework.context.annotation.Conditional;
+import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.security.authentication.ReactiveAuthenticationManager;
 import org.springframework.security.config.annotation.web.reactive.EnableWebFluxSecurity;
 import org.springframework.security.core.userdetails.ReactiveUserDetailsService;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
 import org.springframework.security.web.server.SecurityWebFilterChain;
 import org.springframework.security.web.server.WebFilterChainProxy;
 import org.springframework.web.reactive.config.WebFluxConfigurer;
@@ -52,33 +52,21 @@ import org.springframework.web.reactive.config.WebFluxConfigurer;
 @ConditionalOnClass({ Flux.class, EnableWebFluxSecurity.class, WebFilterChainProxy.class, WebFluxConfigurer.class })
 public class ReactiveSecurityAutoConfiguration {
 
-	@Configuration(proxyBeanMethods = false)
-	@ConditionalOnMissingBean(WebFilterChainProxy.class)
 	@ConditionalOnWebApplication(type = ConditionalOnWebApplication.Type.REACTIVE)
-	@Conditional(EnableWebFluxSecurityCondition.class)
-	@EnableWebFluxSecurity
-	static class EnableWebFluxSecurityConfiguration {
+	@Configuration(proxyBeanMethods = false)
+	class SpringBootWebFluxSecurityConfiguration {
 
-	}
-
-	static final class EnableWebFluxSecurityCondition extends AnyNestedCondition {
-
-		EnableWebFluxSecurityCondition() {
-			super(ConfigurationPhase.REGISTER_BEAN);
+		@Bean
+		@ConditionalOnMissingBean({ ReactiveAuthenticationManager.class, ReactiveUserDetailsService.class,
+				SecurityWebFilterChain.class })
+		ReactiveAuthenticationManager denyAllAuthenticationManager() {
+			return (authentication) -> Mono.error(new UsernameNotFoundException(authentication.getName()));
 		}
 
-		@ConditionalOnBean(ReactiveAuthenticationManager.class)
-		static final class ConditionalOnReactiveAuthenticationManagerBean {
-
-		}
-
-		@ConditionalOnBean(ReactiveUserDetailsService.class)
-		static final class ConditionalOnReactiveUserDetailsService {
-
-		}
-
-		@ConditionalOnBean(SecurityWebFilterChain.class)
-		static final class ConditionalOnSecurityWebFilterChain {
+		@Configuration(proxyBeanMethods = false)
+		@ConditionalOnMissingBean(WebFilterChainProxy.class)
+		@EnableWebFluxSecurity
+		static class EnableWebFluxSecurityConfiguration {
 
 		}
 
diff --git a/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/oauth2/resource/reactive/ReactiveOAuth2ResourceServerAutoConfigurationTests.java b/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/oauth2/resource/reactive/ReactiveOAuth2ResourceServerAutoConfigurationTests.java
index 9583efcbc4..e8165ee189 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/oauth2/resource/reactive/ReactiveOAuth2ResourceServerAutoConfigurationTests.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/oauth2/resource/reactive/ReactiveOAuth2ResourceServerAutoConfigurationTests.java
@@ -740,6 +740,7 @@ class ReactiveOAuth2ResourceServerAutoConfigurationTests {
 			.isEqualTo("aud");
 	}
 
+	@EnableWebFluxSecurity
 	static class TestConfig {
 
 		@Bean
@@ -781,7 +782,6 @@ class ReactiveOAuth2ResourceServerAutoConfigurationTests {
 
 	}
 
-	@EnableWebFluxSecurity
 	@Configuration(proxyBeanMethods = false)
 	static class SecurityWebFilterChainConfig {
 
diff --git a/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/reactive/ReactiveSecurityAutoConfigurationTests.java b/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/reactive/ReactiveSecurityAutoConfigurationTests.java
index dd5dd07ef3..006f7b228f 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/reactive/ReactiveSecurityAutoConfigurationTests.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/reactive/ReactiveSecurityAutoConfigurationTests.java
@@ -20,7 +20,6 @@ import org.junit.jupiter.api.Test;
 import reactor.core.publisher.Flux;
 
 import org.springframework.boot.autoconfigure.AutoConfigurations;
-import org.springframework.boot.autoconfigure.security.reactive.ReactiveSecurityAutoConfiguration.EnableWebFluxSecurityConfiguration;
 import org.springframework.boot.test.context.FilteredClassLoader;
 import org.springframework.boot.test.context.runner.ReactiveWebApplicationContextRunner;
 import org.springframework.context.annotation.Bean;
@@ -53,28 +52,36 @@ class ReactiveSecurityAutoConfigurationTests {
 	}
 
 	@Test
-	void backsOffWhenReactiveAuthenticationManagerNotPresent() {
+	void autoConfiguresDenyAllReactiveAuthenticationManagerWhenNoAlternativeIsAvailable() {
 		this.contextRunner.run((context) -> assertThat(context).hasSingleBean(ReactiveSecurityAutoConfiguration.class)
-			.doesNotHaveBean(EnableWebFluxSecurityConfiguration.class));
+			.hasBean("denyAllAuthenticationManager"));
 	}
 
 	@Test
 	void enablesWebFluxSecurityWhenUserDetailsServiceIsPresent() {
-		this.contextRunner.withUserConfiguration(UserDetailsServiceConfiguration.class)
-			.run((context) -> assertThat(context).getBean(WebFilterChainProxy.class).isNotNull());
+		this.contextRunner.withUserConfiguration(UserDetailsServiceConfiguration.class).run((context) -> {
+			assertThat(context).hasSingleBean(WebFilterChainProxy.class);
+			assertThat(context).doesNotHaveBean("denyAllAuthenticationManager");
+		});
 	}
 
 	@Test
 	void enablesWebFluxSecurityWhenReactiveAuthenticationManagerIsPresent() {
 		this.contextRunner
 			.withBean(ReactiveAuthenticationManager.class, () -> mock(ReactiveAuthenticationManager.class))
-			.run((context) -> assertThat(context).getBean(WebFilterChainProxy.class).isNotNull());
+			.run((context) -> {
+				assertThat(context).hasSingleBean(WebFilterChainProxy.class);
+				assertThat(context).doesNotHaveBean("denyAllAuthenticationManager");
+			});
 	}
 
 	@Test
 	void enablesWebFluxSecurityWhenSecurityWebFilterChainIsPresent() {
 		this.contextRunner.withBean(SecurityWebFilterChain.class, () -> mock(SecurityWebFilterChain.class))
-			.run((context) -> assertThat(context).getBean(WebFilterChainProxy.class).isNotNull());
+			.run((context) -> {
+				assertThat(context).hasSingleBean(WebFilterChainProxy.class);
+				assertThat(context).doesNotHaveBean("denyAllAuthenticationManager");
+			});
 	}
 
 	@Test