diff --git a/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/route/CompositeRouteDefinitionLocator.java b/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/route/CompositeRouteDefinitionLocator.java
index 4cafd929..18d929b0 100644
--- a/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/route/CompositeRouteDefinitionLocator.java
+++ b/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/route/CompositeRouteDefinitionLocator.java
@@ -49,7 +49,8 @@ public class CompositeRouteDefinitionLocator implements RouteDefinitionLocator {
 
 	@Override
 	public Flux<RouteDefinition> getRouteDefinitions() {
-		return this.delegates.flatMap(RouteDefinitionLocator::getRouteDefinitions)
+		return this.delegates
+				.flatMapSequential(RouteDefinitionLocator::getRouteDefinitions)
 				.flatMap(routeDefinition -> {
 					if (routeDefinition.getId() == null) {
 						return randomId().map(id -> {
diff --git a/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/route/CompositeRouteLocator.java b/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/route/CompositeRouteLocator.java
index 13e1f7ce..a58dce30 100644
--- a/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/route/CompositeRouteLocator.java
+++ b/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/route/CompositeRouteLocator.java
@@ -31,7 +31,7 @@ public class CompositeRouteLocator implements RouteLocator {
 
 	@Override
 	public Flux<Route> getRoutes() {
-		return this.delegates.flatMap(RouteLocator::getRoutes);
+		return this.delegates.flatMapSequential(RouteLocator::getRoutes);
 	}
 
 }