Sir Alex Ferguson is waiting to discover the extent of Javier Hernandez's injury after describing Ashley Cole's challenge on the Manchester United striker as 'absolutely shocking'.
Hernandez hobbled from the field of play in the closing 15 minutes of United's 3-1 victory over title rivals Chelsea at Old Trafford on Sunday.
The Mexican was caught on the shin by Cole as he attempted to convert the rebound after team-mate Wayne Rooney's shot had struck the post.
Referee Phil Dowd, after consulting his assistant, showed Cole a yellow card for the tackle, but did not award United a second penalty of the game.
Ferguson believes Hernandez will be out for at least a fortnight and was critical of Cole's challenge, in addition to being surprised by Dowd's decision not to give a spot-kick.
"I don't know what we're going to do," Ferguson told Sky Sports 1.
"To me it was a shocking tackle, an absolutely shocking tackle.
"The referee has booked him, but if he's booked him, I don't know why it wasn't a penalty. I must ask him.
"We're going to have to wait until the morning. At the moment his leg is very numb and he doesn't have any feeling, so he could be out for a couple of weeks maybe."
Did Ashley Cole deserve to be sent off for his tackle on Javier Hernandez?