Alienating or even marginalizing the individual is the worst thing you could do. You need to act soon and make sure it is the right decision. It is bad for mora

Alienating or even marginalizing the individual is the worst thing you could do. You need to act soon and make sure it is the right decision. It is bad for morale for the rest of your team to have 'the common enemy' even if it gives something to share. That being said, booting off the person may not be the best course. He has to be good at something or this would have come up sooner right? Leverage his strengths if you can. If your manager is competent, have him address the individual in the context of self-improvement. This can be a great way to re-motivate someone or send a signal that things are not working out. In any case, act soon and with tact. The last thing you want is an angry and incompetent person on your team.