Aston Villa manager Martin O'Neill has admitted midfielder Stiliyan Petrov is suffering from a crisis of confidence.

O'Neill has persevered with the Bulgarian international since his £6 million move from Celtic 18 months ago despite the player only occasionally showing his best form.

But he substituted him at half-time after an ineffective opening 45 minutes against Newcastle on Saturday and replaced him with youngster Craig Gardner.  Villa went on to win the game 4-1 with a dynamic second half performance.

"Stiliyan is a very good player but I've seen little spells before where he was also lacking in confidence at Celtic," O'Neill said. "He wants to do well but the early chance he had against Newcastle showed how he is feeling at present.

"The Stiliyan Petrov I know, the fully confident one, when someone laid the ball back to him in the outside right position, would not have whipped in his shot first time and miscued it.

"A Stiliyan Petrov with confidence wouldn't have done that. I know what he is capable of. He's scored goals for Celtic, including goals at European level.

"Yes, I'm asking him to play a different role at the moment but it's something that he is going to have to live with."

O'Neill will try to repair Petrov's confidence during the current sunshine break in Spain.

Skipper Gareth Barry believes a few days training in the sun in a different environment will help to recharge the batteries of the smallest squad in the Barclays Premier League.

The England midfielder said: "It has been a long season and, of course, the festive season was busy. There have been a lot of games this season. Of course, you want to play every week but I'm sure it will be good for the team to have this break away.

"We have some young players who are playing their second consecutive busy season and they need a rest.

"It did us good when we did something similar last season and we came back and finished very strongly with a nine-game unbeaten run. Hopefully the same will happen again for us."