AW: If you are still close friends, it is important for you to have a conversation with him. You need to express that you went out on a limb for him and that your reputation is at stake. It is possible that he doesn't know that his performance/reputation is poor and that you can be of assistance. I would also recommend that you would follow up with the hiring manager and see if there is anything you could do to turn the situation around while salvaging your relationship with the manager who trusted your recommendation.