Gary Megson has admitted that a change in formation against Arsenal last Saturday has given him 'food for thought' ahead of this weekend's trip to Old Trafford.

The Bolton manager switched from his conventional 4-5-1 system by playing two forwards for long periods against the Gunners in an attempt to create more in the final third and reduce the visitors' time on the ball.

Kevin Davies was partnered by debutant Ebi Smolarek in attack before Riga replaced the Poland international early in the second period.

And with Johan Elmander now back in contention following a month-long spell on the sidelines with a hamstring problem, Megson could be tempted to operate in a similar style against the Red Devils, but only if it doesn't leave his team vulnerable in other areas of the pitch.

"I was pleasantly surprised because this club has had a formation that it has stuck with for quite a long time now," said Megson on his change in tactics against Arsenal.

"Systems and tactics are nothing on their own because you have to have the right players to be able to play in that formation.

"In playing with the two upfront for an hour last Saturday we created a lot more and the ball stayed in the opposition's half for a lot longer. There was a lot more movement, a lot more crosses and a lot of good things about it.

"But it's swings and roundabouts because if we do play like that then we have to make sure that we don't become easy to play against going the other way.

"We'll try and attack, but we have to have the right players and they have to be available. It's food for thought."