Dimitar Berbatov will miss Manchester United's Champions League clash with Porto on Tuesday after being ruled out for two weeks with an ankle injury.

The Bulgarian was hurt during the 2-0 defeat at Fulham two weeks ago and pulled out of his country's World Cup qualifiers this week.

He will play no part in Sunday's League clash against Aston Villa leaving Sir Alex Ferguson with selection problems in attack as Wayne Rooney is suspended and Carlos Tevez faces a gruelling journey back from Argentina duty in Bolivia.

“I think he gets back from Mars this evening,” joked United boss Ferguson. “Hopefully, Carlos will be okay. That will give us one striker, then we will have to choose another.

“It's probably going to be another two weeks for Dimitar. Hopefully he will be back training with us at the end of next week.”

United will be knocked off the top of the table if Liverpool beat Fulham tomorrow but Ferguson said: “I don't worry about that. I concentrate and focus on Manchester United.”