diff --git a/pkg/apis/apps/validation/validation.go b/pkg/apis/apps/validation/validation.go
index 4699e85b98f..ab68809bf0f 100644
--- a/pkg/apis/apps/validation/validation.go
+++ b/pkg/apis/apps/validation/validation.go
@@ -146,21 +146,15 @@ func ValidateStatefulSet(statefulSet *apps.StatefulSet, opts apivalidation.PodVa
 func ValidateStatefulSetUpdate(statefulSet, oldStatefulSet *apps.StatefulSet) field.ErrorList {
 	allErrs := apivalidation.ValidateObjectMetaUpdate(&statefulSet.ObjectMeta, &oldStatefulSet.ObjectMeta, field.NewPath("metadata"))
 
-	restoreReplicas := statefulSet.Spec.Replicas
-	statefulSet.Spec.Replicas = oldStatefulSet.Spec.Replicas
-
-	restoreTemplate := statefulSet.Spec.Template
-	statefulSet.Spec.Template = oldStatefulSet.Spec.Template
-
-	restoreStrategy := statefulSet.Spec.UpdateStrategy
-	statefulSet.Spec.UpdateStrategy = oldStatefulSet.Spec.UpdateStrategy
-
-	if !apiequality.Semantic.DeepEqual(statefulSet.Spec, oldStatefulSet.Spec) {
+	// statefulset updates aren't super common and general updates are likely to be touching spec, so we'll do this
+	// deep copy right away.  This avoids mutating our inputs
+	newStatefulSetClone := statefulSet.DeepCopy()
+	newStatefulSetClone.Spec.Replicas = oldStatefulSet.Spec.Replicas             // +k8s:verify-mutation:reason=clone
+	newStatefulSetClone.Spec.Template = oldStatefulSet.Spec.Template             // +k8s:verify-mutation:reason=clone
+	newStatefulSetClone.Spec.UpdateStrategy = oldStatefulSet.Spec.UpdateStrategy // +k8s:verify-mutation:reason=clone
+	if !apiequality.Semantic.DeepEqual(newStatefulSetClone.Spec, oldStatefulSet.Spec) {
 		allErrs = append(allErrs, field.Forbidden(field.NewPath("spec"), "updates to statefulset spec for fields other than 'replicas', 'template', and 'updateStrategy' are forbidden"))
 	}
-	statefulSet.Spec.Replicas = restoreReplicas
-	statefulSet.Spec.Template = restoreTemplate
-	statefulSet.Spec.UpdateStrategy = restoreStrategy
 
 	allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(statefulSet.Spec.Replicas), field.NewPath("spec", "replicas"))...)
 	return allErrs