Fàbregas out, Rooney doubt

Cesc Fàbregas has been ruled out of Arsenal FC's UEFA Champions League first knockout round second leg against FC Porto on Tuesday, manager Arsène Wenger has confirmed.

The Arsenal captain opened the scoring in Arsenal's 3-1 victory against Burnley FC on Saturday, but was then replaced six minutes before the break by Abou Diaby. "He has a hamstring injury and we cannot even take a gamble," said Wenger, whose team must overturn a 2-1 deficit.

"We don't know how long he's going to be out for. He's having a scan today. We are convinced it will be a short time. He has a small chance to be back at the weekend against Hull, but to play him [on Tuesday] would risk significant damage in the muscle. It's a recurrence of the same hamstring so we must find out why the hamstring is causing him problems."

Manchester United FC striker Wayne Rooney, meanwhile, is doubtful for his side's second leg against AC Milan on Wednesday. Rooney, who missed the 1-0 win at Wolverhampton Wanderers FC on Saturday because of a knee problem aggravated while on England duty, is rated "very doubtful" by United manager Sir Alex Ferguson. The striker scored two headers in the first leg, which United won 3-2.

For Milan, both Pato and Clarence Seedorf have been passed fit to travel to Manchester following thigh injuries. Seedorf is expected to start the game, with Pato on the bench. Neither played in Saturday evening's goalless draw with AS Roma.