Arsenal boss Arsene Wenger is sweating on the fitness of Robin van Persie for tomorrow's clash with Manchester United.
Van Persie has not played since suffering a groin injury in the 2-1 FA Cup semi-final defeat by Chelsea and has missed Arsenal's last four games.
But Wenger wants to revert to an attacking 4-4-2 formation and will give the silky Dutchman every chance to prove his fitness.
The Gunners boss said: "We played 4-4-2 at Portsmouth on Saturday and I think we look more threatening that way.
"Maybe we will play with two strikers against Manchester United - but the way we line up depends on who is available. When Cesc Fabregas plays behind the striker, as he did at Old Trafford last week, the striker looks to be a little isolated.
"But when we play with Theo Walcott on the right, he is more of a winger than a midfielder so the rest of the side need to be more defensive. So it is important we get the balance of our team right."
