diff --git a/staging/src/k8s.io/apiserver/pkg/admission/configuration/mutating_webhook_manager.go b/staging/src/k8s.io/apiserver/pkg/admission/configuration/mutating_webhook_manager.go
index db88e1ade31..76c11f4a618 100644
--- a/staging/src/k8s.io/apiserver/pkg/admission/configuration/mutating_webhook_manager.go
+++ b/staging/src/k8s.io/apiserver/pkg/admission/configuration/mutating_webhook_manager.go
@@ -53,7 +53,8 @@ var _ generic.Source = &mutatingWebhookConfigurationManager{}
 func NewMutatingWebhookConfigurationManager(f informers.SharedInformerFactory) generic.Source {
 	informer := f.Admissionregistration().V1().MutatingWebhookConfigurations()
 	manager := &mutatingWebhookConfigurationManager{
-		lister: informer.Lister(),
+		lister:                        informer.Lister(),
+		createMutatingWebhookAccessor: webhook.NewMutatingWebhookAccessor,
 	}
 	manager.lazy.Evaluate = manager.getConfiguration