How to disable autosync for Gmail app?

So is there any way to disable autosync for Gmail app, not bult-in Mail app?

I do not want app to constantly check for new emails but when I open it and manually refresh.

I can disable notifications but app will still be syncing and when I open it new emails are alredy there, so not option.

Please, do not point me to "how to dissable push in Mail app" as that will not solve my issue.

Thanks, Milan.