The central defender lasted just four minutes of Wednesday night's 1-1 draw at Everton and boss Arsene Wenger told the media after the game that he expects the player to be out for at least three weeks.
Meanwhile Wenger was delighted to take a point away from Goodison Park despite the fact they squandered the lead after Theo Walcott had given them the perfect start in the opening minute.
Marouane Fellaini equalised for the home side in the 28th minute and although Wenger was unhappy with the manner it was conceded he was pleased to take a point.
"It was a game of big physical intensity, we had a good start and after that I felt Everton came back into it and their direct game was always a threat," he said.
"There are regrets on the goal we conceded but 1-1 is a fair result and it is a good point here. We needed to show great spirit to get away with a point and I am pleased with the effort they put into the game."