Best plugin to backup WP data for a specific site in multisite network?

I am looking for a solution (plugin hopefully) that will allow an admin to schedule a weekly database backup for their specific site(blog) only that is in a larger multisite network? I have am using WP-DBManager for the entire database, but if a site admin uses it, it seems that he can backup the entire multisite database?

Looking forward to hearing anyone’s thoughts on this.

Thanks in advance.