Aston Villa will step up security for tonight's UEFA Cup tie against Ajax following the coin-throwing incident last weekend.

Linesman Phil Sharp needed treatment after being hit by a coin thrown from the crowd during the goalless draw with Portsmouth.

A Villa spokesman said: "There will be a small additional police presence at Villa Park in light of Saturday's events. There will also be additional camera surveilance by the club and by the police."

Stiliyan Petrov, meanwhile, goes into tonight's game admitting Villa fans were right to boo him during his early struggles at the club.

The Bulgarian is now a key figure in midfield having overcome the problems which initially marred his £6million move from Celtic in 2006.

Petrov said: "To be honest, the fans were right with their reaction towards me.

"I was a big signing, I cost a lot of money, and they expect a lot from you. If I don't produce then, of course, they will be on my back."

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