diff --git a/pkg/endpoints/openapi/openapi.go b/pkg/endpoints/openapi/openapi.go
index 7b8f3589e..e512f29b3 100644
--- a/pkg/endpoints/openapi/openapi.go
+++ b/pkg/endpoints/openapi/openapi.go
@@ -143,12 +143,24 @@ func typeName(t reflect.Type) string {
 }
 
 // NewDefinitionNamer constructs a new DefinitionNamer to be used to customize OpenAPI spec.
-func NewDefinitionNamer(s *runtime.Scheme) DefinitionNamer {
-	ret := DefinitionNamer{
+func NewDefinitionNamer(schemes ...*runtime.Scheme) *DefinitionNamer {
+	ret := &DefinitionNamer{
 		typeGroupVersionKinds: map[string]groupVersionKinds{},
 	}
-	for gvk, rtype := range s.AllKnownTypes() {
-		ret.typeGroupVersionKinds[typeName(rtype)] = append(ret.typeGroupVersionKinds[typeName(rtype)], gvkConvert(gvk))
+	for _, s := range schemes {
+		for gvk, rtype := range s.AllKnownTypes() {
+			newGVK := gvkConvert(gvk)
+			exists := false
+			for _, existingGVK := range ret.typeGroupVersionKinds[typeName(rtype)] {
+				if newGVK == existingGVK {
+					exists = true
+					break
+				}
+			}
+			if !exists {
+				ret.typeGroupVersionKinds[typeName(rtype)] = append(ret.typeGroupVersionKinds[typeName(rtype)], newGVK)
+			}
+		}
 	}
 	for _, gvk := range ret.typeGroupVersionKinds {
 		sort.Sort(gvk)
diff --git a/pkg/server/config.go b/pkg/server/config.go
index eb1c27d14..75a2b5dcc 100644
--- a/pkg/server/config.go
+++ b/pkg/server/config.go
@@ -278,8 +278,7 @@ func NewRecommendedConfig(codecs serializer.CodecFactory) *RecommendedConfig {
 	}
 }
 
-func DefaultOpenAPIConfig(getDefinitions openapicommon.GetOpenAPIDefinitions, scheme *runtime.Scheme) *openapicommon.Config {
-	defNamer := apiopenapi.NewDefinitionNamer(scheme)
+func DefaultOpenAPIConfig(getDefinitions openapicommon.GetOpenAPIDefinitions, defNamer *apiopenapi.DefinitionNamer) *openapicommon.Config {
 	return &openapicommon.Config{
 		ProtocolList:   []string{"https"},
 		IgnorePrefixes: []string{"/swaggerapi"},
diff --git a/pkg/server/genericapiserver_test.go b/pkg/server/genericapiserver_test.go
index 4b6e7b7dd..fbe7235c2 100644
--- a/pkg/server/genericapiserver_test.go
+++ b/pkg/server/genericapiserver_test.go
@@ -44,6 +44,7 @@ import (
 	"k8s.io/apiserver/pkg/authorization/authorizer"
 	"k8s.io/apiserver/pkg/endpoints/discovery"
 	genericapifilters "k8s.io/apiserver/pkg/endpoints/filters"
+	openapinamer "k8s.io/apiserver/pkg/endpoints/openapi"
 	"k8s.io/apiserver/pkg/registry/rest"
 	genericfilters "k8s.io/apiserver/pkg/server/filters"
 	"k8s.io/client-go/informers"
@@ -95,7 +96,7 @@ func setUp(t *testing.T) (Config, *assert.Assertions) {
 		t.Fatal("unable to create fake client set")
 	}
 
-	config.OpenAPIConfig = DefaultOpenAPIConfig(testGetOpenAPIDefinitions, runtime.NewScheme())
+	config.OpenAPIConfig = DefaultOpenAPIConfig(testGetOpenAPIDefinitions, openapinamer.NewDefinitionNamer(runtime.NewScheme()))
 	config.OpenAPIConfig.Info.Version = "unversioned"
 	config.SwaggerConfig = DefaultSwaggerConfig()
 	sharedInformers := informers.NewSharedInformerFactory(clientset, config.LoopbackClientConfig.Timeout)