Aston Villa No2 John Robertson says striker John Carew is as dangerous as any attacker in the game.

"He's a handful. In my opinion when he is on song he is as good as anyone there is in the game. He is a big lad who is extremely strong but he has no shortage of ability," said Robertson.

"He has good feet and can play a bit, that's for sure.

''He also has a fair bit of pace about him and he can hold the ball up and bring other players into play. That's his biggest asset - his major strength. John has been terrific for us this season. It will be difficult for the Scotland boys at the back. Whatever they do they'll need to keep a close eye on Carew.

"He'll lean back into them and try to throw his weight around. The less he gets of the ball the less harm he can do though.

"So that means try to stop the service into him. He obviously relies on service so that could be the key."