Celtic took the lead when Shunsuke Nakamura curled in a magnificent free-kick after 48 minutes.

And when United captain Barry Robson was dismissed in the 89th minute for head-butting Lee Naylor off the ball the home side's hopes looked forlorn.

But striker Jon Daly scored two minutes into injury time with a terrific half-volley, as Celtic's disappointing recent form - which saw them lose to Rangers and Falkirk in their previous two games - remained a worry for boss Gordon Strachan.