Chinese or not

Employees usually are given the 2nd or even 3rd opportunity before letting go. So if I were you, I'd make it crystal clear to the chinese guy that he is being given the last opportunity and he needs to show everyone including your boss that he is capalbe fo doing his job within a certain timeframe. He needs to realize that this time things are serious, and you won't be able to protect him any more.

If you'd like to be more helpful, sit down with him on specific areas he needs to improve immediately. What tasks he should be able to do and present to management right away.