With Alan Pardew up in the stands because of his two-game ban for oushing a linesman, John Carver was in the dugout taking calls from the manager's phone.
It was thought Pardew wanted Obertan to go on with only a minute remaining of injury time, but the former Manchester United refused and Carver switched to Bigirimana.
However - a United source has dismissed the talk saying: " Obertan did NOT refuse to come on as a late substitute."