diff --git a/cli/command/system/cmd.go b/cli/command/system/cmd.go
index 455387cd46..60979e7224 100644
--- a/cli/command/system/cmd.go
+++ b/cli/command/system/cmd.go
@@ -18,8 +18,8 @@ func NewSystemCommand(dockerCli *command.DockerCli) *cobra.Command {
 	cmd.AddCommand(
 		NewEventsCommand(dockerCli),
 		NewInfoCommand(dockerCli),
-		NewDiskUsageCommand(dockerCli),
-		NewPruneCommand(dockerCli),
+		newDiskUsageCommand(dockerCli),
+		newPruneCommand(dockerCli),
 	)
 
 	return cmd
diff --git a/cli/command/system/df.go b/cli/command/system/df.go
index d8f9bdc021..5146482f0e 100644
--- a/cli/command/system/df.go
+++ b/cli/command/system/df.go
@@ -15,8 +15,8 @@ type diskUsageOptions struct {
 	format  string
 }
 
-// NewDiskUsageCommand creates a new cobra.Command for `docker df`
-func NewDiskUsageCommand(dockerCli *command.DockerCli) *cobra.Command {
+// newDiskUsageCommand creates a new cobra.Command for `docker df`
+func newDiskUsageCommand(dockerCli *command.DockerCli) *cobra.Command {
 	var opts diskUsageOptions
 
 	cmd := &cobra.Command{
diff --git a/cli/command/system/prune.go b/cli/command/system/prune.go
index d542391224..c86025fc1f 100644
--- a/cli/command/system/prune.go
+++ b/cli/command/system/prune.go
@@ -26,8 +26,8 @@ type pruneOptions struct {
 	filter          opts.FilterOpt
 }
 
-// NewPruneCommand creates a new cobra.Command for `docker prune`
-func NewPruneCommand(dockerCli command.Cli) *cobra.Command {
+// newPruneCommand creates a new cobra.Command for `docker prune`
+func newPruneCommand(dockerCli command.Cli) *cobra.Command {
 	options := pruneOptions{filter: opts.NewFilterOpt(), pruneBuildCache: true}
 
 	cmd := &cobra.Command{
diff --git a/cli/command/system/prune_test.go b/cli/command/system/prune_test.go
index 980a93865f..669166c998 100644
--- a/cli/command/system/prune_test.go
+++ b/cli/command/system/prune_test.go
@@ -9,7 +9,7 @@ import (
 
 func TestPrunePromptPre131(t *testing.T) {
 	cli := test.NewFakeCli(&fakeClient{version: "1.30"})
-	cmd := NewPruneCommand(cli)
+	cmd := newPruneCommand(cli)
 	assert.NoError(t, cmd.Execute())
 	assert.NotContains(t, cli.OutBuffer().String(), "all build cache")
 }