Manchester United are sweating on the fitness of Danny Welbeck after the forward left the Etihad Stadium wearing a protective boot on Monday night.
Welbeck, 21, was on the receiving end of a crunching challenge from Nigel de Jong in the second half of Manchester City's 1-0 victory over their rivals United that put them back top of the table on goal difference.
The tackle sparked a feisty confrontation between managerial counterparts Roberto Mancini and Sir Alex Ferguson, with the latter accusing the former of "badgering" the officials throughout the match.
Ferguson's misery looks to have been compounded amid fears over Welbeck's fitness, with the striker a doubt for United's final two Premier League matches of the season against Swansea and Sunderland. The news will also be of concern to Roy Hodgson, who looks set to be named England manager ahead of Euro 2012.
Welbeck has featured regularly for the Red Devils this season, making 30 league appearances and scoring nine goals.