diff --git a/api/types/fix.go b/api/types/fix.go
index 71548bea5..de70467ed 100644
--- a/api/types/fix.go
+++ b/api/types/fix.go
@@ -9,14 +9,14 @@ import (
 	"sigs.k8s.io/yaml"
 )
 
-// FixKustomizationPreUnmarshalling modies the raw data
+// FixKustomizationPreUnmarshalling modifies the raw data
 // before marshalling - e.g. changes old field names to
 // new field names.
 func FixKustomizationPreUnmarshalling(data []byte) ([]byte, error) {
-	deprecateFieldsMap := map[string]string{
+	deprecatedFieldsMap := map[string]string{
 		"imageTags:": "images:",
 	}
-	for oldname, newname := range deprecateFieldsMap {
+	for oldname, newname := range deprecatedFieldsMap {
 		pattern := regexp.MustCompile(oldname)
 		data = pattern.ReplaceAll(data, []byte(newname))
 	}
diff --git a/api/types/kustomization.go b/api/types/kustomization.go
index 8cc7299b7..c32832b2c 100644
--- a/api/types/kustomization.go
+++ b/api/types/kustomization.go
@@ -144,6 +144,7 @@ type Kustomization struct {
 // moving content of deprecated fields to newer
 // fields.
 func (k *Kustomization) FixKustomizationPostUnmarshalling() {
+
 	if k.Kind == "" {
 		k.Kind = KustomizationKind
 	}
@@ -158,6 +159,17 @@ func (k *Kustomization) FixKustomizationPostUnmarshalling() {
 	k.Bases = nil
 }
 
+// FixKustomizationPreMarshalling fixes things
+// that should occur after the kustomization file
+// has been processed.
+func (k *Kustomization) FixKustomizationPreMarshalling() {
+	// PatchesJson6902 should be under the Patches field.
+	for _, patch := range k.PatchesJson6902 {
+		k.Patches = append(k.Patches, patch.ToPatch())
+	}
+	k.PatchesJson6902 = nil
+}
+
 func (k *Kustomization) EnforceFields() []string {
 	var errs []string
 	if k.Kind != "" && k.Kind != KustomizationKind && k.Kind != ComponentKind {
diff --git a/api/types/patchjson6902.go b/api/types/patchjson6902.go
index 1a189aa6d..4c90ce201 100644
--- a/api/types/patchjson6902.go
+++ b/api/types/patchjson6902.go
@@ -19,3 +19,9 @@ type PatchJson6902 struct {
 	// inline patch string
 	Patch string `json:"patch,omitempty" yaml:"patch,omitempty"`
 }
+
+// ToPatch converts a PatchJson6902 to its superset Patch.
+func (patch *PatchJson6902) ToPatch() Patch {
+	selector := patch.Target.ToSelector()
+	return Patch{Path: patch.Path, Patch: patch.Patch, Target: &selector}
+}
diff --git a/api/types/patchtarget.go b/api/types/patchtarget.go
index ee8c6a691..85f804574 100644
--- a/api/types/patchtarget.go
+++ b/api/types/patchtarget.go
@@ -13,3 +13,8 @@ type PatchTarget struct {
 	Namespace string `json:"namespace,omitempty" yaml:"namespace,omitempty"`
 	Name      string `json:"name" yaml:"name"`
 }
+
+// ToSelector converts a PatchTarget to a Selector.
+func (target *PatchTarget) ToSelector() Selector {
+	return Selector{Name: target.Name, Namespace: target.Namespace, Gvk: target.Gvk}
+}
diff --git a/kustomize/go.mod b/kustomize/go.mod
index 74cc82e42..fc49b66c4 100644
--- a/kustomize/go.mod
+++ b/kustomize/go.mod
@@ -3,6 +3,7 @@ module sigs.k8s.io/kustomize/kustomize/v3
 go 1.14
 
 require (
+	github.com/google/go-cmp v0.3.0
 	github.com/pkg/errors v0.9.1
 	github.com/spf13/cobra v1.0.0
 	github.com/spf13/pflag v1.0.5
diff --git a/kustomize/go.sum b/kustomize/go.sum
index 214137f73..230ea3a57 100644
--- a/kustomize/go.sum
+++ b/kustomize/go.sum
@@ -239,6 +239,7 @@ github.com/google/btree v1.0.0/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/google/go-cmp v0.3.0 h1:crn/baboCvb5fXaQ0IJ1SGTsTVrWpDsCWC8EGETZijY=
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
+github.com/google/go-cmp v0.5.1 h1:JFrFEBb2xKufg6XkJsJr+WbKb4FQlURi5RUcBveYu9k=
 github.com/google/gofuzz v0.0.0-20161122191042-44d81051d367/go.mod h1:HP5RmnzzSNb993RKQDq4+1A4ia9nllfqcQFTQJedwGI=
 github.com/google/gofuzz v1.0.0 h1:A8PeW59pxE9IoFRqBp37U+mSNaQoZ46F1f0f863XSXw=
 github.com/google/gofuzz v1.0.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
diff --git a/kustomize/internal/commands/kustfile/kustomizationfile.go b/kustomize/internal/commands/kustfile/kustomizationfile.go
index f347e368a..900d748e2 100644
--- a/kustomize/internal/commands/kustfile/kustomizationfile.go
+++ b/kustomize/internal/commands/kustfile/kustomizationfile.go
@@ -170,6 +170,7 @@ func (mf *kustomizationFile) Write(kustomization *types.Kustomization) error {
 	if kustomization == nil {
 		return errors.New("util: kustomization file arg is nil")
 	}
+	kustomization.FixKustomizationPreMarshalling()
 	data, err := mf.marshal(kustomization)
 	if err != nil {
 		return err
diff --git a/kustomize/internal/commands/kustfile/kustomizationfile_test.go b/kustomize/internal/commands/kustfile/kustomizationfile_test.go
index 2f9e9e69b..97bcc7655 100644
--- a/kustomize/internal/commands/kustfile/kustomizationfile_test.go
+++ b/kustomize/internal/commands/kustfile/kustomizationfile_test.go
@@ -8,6 +8,8 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/google/go-cmp/cmp"
+
 	"sigs.k8s.io/kustomize/api/filesys"
 	"sigs.k8s.io/kustomize/api/konfig"
 	"sigs.k8s.io/kustomize/api/types"
@@ -158,8 +160,8 @@ patchesStrategicMerge:
 	}
 	bytes, _ := fSys.ReadFile(mf.path)
 
-	if !reflect.DeepEqual(kustomizationContentWithComments, bytes) {
-		t.Fatal("written kustomization with comments is not the same as original one")
+	if diff := cmp.Diff(kustomizationContentWithComments, bytes); diff != "" {
+		t.Errorf("Mismatch (-expected, +actual):\n%s", diff)
 	}
 }
 
@@ -252,10 +254,8 @@ generatorOptions:
 	}
 	bytes, _ := fSys.ReadFile(mf.path)
 
-	if string(expected) != string(bytes) {
-		t.Fatalf(
-			"expected =\n%s\n\nactual =\n%s\n",
-			string(expected), string(bytes))
+	if diff := cmp.Diff(expected, bytes); diff != "" {
+		t.Errorf("Mismatch (-expected, +actual):\n%s", diff)
 	}
 }
 
@@ -290,10 +290,8 @@ kind: Kustomization
 	}
 	bytes, _ := fSys.ReadFile(mf.path)
 
-	if string(expected) != string(bytes) {
-		t.Fatalf(
-			"expected =\n%s\n\nactual =\n%s\n",
-			string(expected), string(bytes))
+	if diff := cmp.Diff(expected, bytes); diff != "" {
+		t.Errorf("Mismatch (-expected, +actual):\n%s", diff)
 	}
 }
 
@@ -335,10 +333,105 @@ kind: Kustomization
 	}
 	bytes, _ := fSys.ReadFile(mf.path)
 
-	if string(expected) != string(bytes) {
-		t.Fatalf(
-			"expected =\n%s\n\nactual =\n%s\n",
-			string(expected), string(bytes))
+	if diff := cmp.Diff(expected, bytes); diff != "" {
+		t.Errorf("Mismatch (-expected, +actual):\n%s", diff)
+	}
+}
+
+func TestRenameAndKeepOutdatedPatchesField(t *testing.T) {
+	kustomizationContentWithOutdatedPatchesFieldTitle := []byte(`
+patchesJson6902:
+- path: patch1.yaml
+  target:
+    kind: Deployment
+patches:
+- path: patch2.yaml
+  target:
+    kind: Deployment
+- path: patch3.yaml
+  target:
+    kind: Service
+`)
+
+	expected := []byte(`
+patches:
+- path: patch2.yaml
+  target:
+    kind: Deployment
+- path: patch3.yaml
+  target:
+    kind: Service
+- path: patch1.yaml
+  target:
+    kind: Deployment
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+`)
+	fSys := filesys.MakeFsInMemory()
+	testutils_test.WriteTestKustomizationWith(fSys, kustomizationContentWithOutdatedPatchesFieldTitle)
+	mf, err := NewKustomizationFile(fSys)
+	if err != nil {
+		t.Fatalf("Unexpected Error: %v", err)
+	}
+
+	kustomization, err := mf.Read()
+	if err != nil {
+		t.Fatalf("Unexpected Error: %v", err)
+	}
+	if err = mf.Write(kustomization); err != nil {
+		t.Fatalf("Unexpected Error: %v", err)
+	}
+	bytes, _ := fSys.ReadFile(mf.path)
+
+	if diff := cmp.Diff(expected, bytes); diff != "" {
+		t.Errorf("Mismatch (-expected, +actual):\n%s", diff)
+	}
+}
+
+func TestFixOutdatedPatchesFieldTitle(t *testing.T) {
+	kustomizationContentWithOutdatedPatchesFieldTitle := []byte(`
+patchesJson6902:
+- path: patch1.yaml
+  target:
+    kind: Service
+- path: patch2.yaml
+  target:
+    group: apps
+    kind: Deployment
+    version: v1
+`)
+
+	expected := []byte(`
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+patches:
+- path: patch1.yaml
+  target:
+    kind: Service
+- path: patch2.yaml
+  target:
+    group: apps
+    kind: Deployment
+    version: v1
+`)
+	fSys := filesys.MakeFsInMemory()
+	testutils_test.WriteTestKustomizationWith(fSys, kustomizationContentWithOutdatedPatchesFieldTitle)
+	mf, err := NewKustomizationFile(fSys)
+	if err != nil {
+		t.Fatalf("Unexpected Error: %v", err)
+	}
+
+	kustomization, err := mf.Read()
+	if err != nil {
+		t.Fatalf("Unexpected Error: %v", err)
+	}
+	if err = mf.Write(kustomization); err != nil {
+		t.Fatalf("Unexpected Error: %v", err)
+	}
+	bytes, _ := fSys.ReadFile(mf.path)
+
+	if diff := cmp.Diff(expected, bytes); diff != "" {
+		t.Errorf("Mismatch (-expected, +actual):\n%s", diff)
 	}
 }