diff --git a/docs/appendices/0.20.0-migration-guide.md b/docs/appendices/0.20.0-migration-guide.md
index 502e7ed4b..be6461359 100644
--- a/docs/appendices/0.20.0-migration-guide.md
+++ b/docs/appendices/0.20.0-migration-guide.md
@@ -28,6 +28,11 @@ The refactor of the proxy plugin removes the following functions from being sour
 
 The informal policy is to allow removal of functions within a `functions` file if they are not used in OSS plugins. Should you be affected by any such removals, please file an issue to expose the functionality via a plugin trigger.
 
+### Function renames
+
+- `tar#tar_in_cmd` was renamed to `tar#cmd-tar-in`. Users should avoid using `cmd-*` commands directly, and instead file an issue to have them exposed via a plugin trigger.
+- `tar#tar_from_cmd` was renamed to `tar#cmd-tar-from`. Users should avoid using `cmd-*` commands directly, and instead file an issue to have them exposed via a plugin trigger.
+
 ### Remove support for Unsupported Operating Systems
 
 Dokku will no longer distribute packages for Ubuntu versions that have reached either End of Life or End of Standard Support (for LTS releases). This currently includes the following releases:
diff --git a/plugins/tar/functions b/plugins/tar/functions
index a5b703d19..781dba69f 100755
--- a/plugins/tar/functions
+++ b/plugins/tar/functions
@@ -75,7 +75,7 @@ cmd-tar-from() {
 
   verify_app_name "$APP"
   shift 2
-  curl -# --insecure -L "$URL" | tar_in_cmd "tar:in" "$APP" "$@"
+  curl -# --insecure -L "$URL" | cmd-tar-in "tar:in" "$APP" "$@"
 }
 
 tar_receive_app() {