diff --git a/testing/fixture.go b/testing/fixture.go
index 3e749782..2bec0ed6 100644
--- a/testing/fixture.go
+++ b/testing/fixture.go
@@ -631,7 +631,7 @@ type managedFieldObjectTracker struct {
 	ObjectTracker
 	scheme          ObjectScheme
 	objectConverter runtime.ObjectConvertor
-	mapper          meta.RESTMapper
+	mapper          func() meta.RESTMapper
 	typeConverter   managedfields.TypeConverter
 }
 
@@ -644,8 +644,10 @@ func NewFieldManagedObjectTracker(scheme *runtime.Scheme, decoder runtime.Decode
 		ObjectTracker:   NewObjectTracker(scheme, decoder),
 		scheme:          scheme,
 		objectConverter: scheme,
-		mapper:          testrestmapper.TestOnlyStaticRESTMapper(scheme),
-		typeConverter:   typeConverter,
+		mapper: func() meta.RESTMapper {
+			return testrestmapper.TestOnlyStaticRESTMapper(scheme)
+		},
+		typeConverter: typeConverter,
 	}
 }
 
@@ -654,7 +656,7 @@ func (t *managedFieldObjectTracker) Create(gvr schema.GroupVersionResource, obj
 	if err != nil {
 		return err
 	}
-	gvk, err := t.mapper.KindFor(gvr)
+	gvk, err := t.mapper().KindFor(gvr)
 	if err != nil {
 		return err
 	}
@@ -698,8 +700,9 @@ func (t *managedFieldObjectTracker) Update(gvr schema.GroupVersionResource, obj
 	if err != nil {
 		return err
 	}
-	gvk, err := t.mapper.KindFor(gvr)
+	gvk, err := t.mapper().KindFor(gvr)
 	if err != nil {
+		println("kindfor")
 		return err
 	}
 	mgr, err := t.fieldManagerFor(gvk)
@@ -728,7 +731,7 @@ func (t *managedFieldObjectTracker) Patch(gvr schema.GroupVersionResource, patch
 	if err != nil {
 		return err
 	}
-	gvk, err := t.mapper.KindFor(gvr)
+	gvk, err := t.mapper().KindFor(gvr)
 	if err != nil {
 		return err
 	}
@@ -757,7 +760,7 @@ func (t *managedFieldObjectTracker) Apply(gvr schema.GroupVersionResource, apply
 	if err != nil {
 		return err
 	}
-	gvk, err := t.mapper.KindFor(gvr)
+	gvk, err := t.mapper().KindFor(gvr)
 	if err != nil {
 		return err
 	}
diff --git a/testing/fixture_test.go b/testing/fixture_test.go
index 2fa67cd6..54c25024 100644
--- a/testing/fixture_test.go
+++ b/testing/fixture_test.go
@@ -661,3 +661,25 @@ var configMapTypedSchema = typed.YAMLObject(`types:
       namedType: __untyped_deduced_
     elementRelationship: separable
 `)
+
+func TestManagedFieldsObjectTrackerReloadsScheme(t *testing.T) {
+	cmResource := schema.GroupVersionResource{Version: "v1", Resource: "configmaps"}
+	scheme := runtime.NewScheme()
+	codecs := serializer.NewCodecFactory(scheme)
+
+	// Create tracker without registered ConfigMap type
+	tracker := NewFieldManagedObjectTracker(scheme, codecs.UniversalDecoder(), configMapTypeConverter(scheme))
+
+	cm := &v1.ConfigMap{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: "test-cm",
+		},
+		Data: map[string]string{"key": "value"},
+	}
+
+	// Register the type in scheme
+	scheme.AddKnownTypes(cmResource.GroupVersion(), &v1.ConfigMap{})
+
+	err := tracker.Create(cmResource, cm, "default", metav1.CreateOptions{FieldManager: "test-manager"})
+	assert.NoError(t, err, "Create should succeed after registering type")
+}