Aston Villa manager David O'Leary is looking to Thomas Sorensen to play a big role in Sunday's Premiership match against Birmingham City at Villa Park and further erase his personal memory bank of bad derby experiences.

Sorensen dropped embarrassing clangers in both of last season's 2-0 derby defeats to Blues.

But the big Dane laid a lot of personal bogeys when he kept a clean sheet to help earn Villa their 1-0 win over Steve Bruce's team at St Andrew's in October.

And, pointing to Sorensen's performance last Sunday against West Bromwich Albion, O'Leary is confident that the keeper can maintain his composure against the bigger psychological test of facing Blues again.

O'Leary said: "All I know is that, if we put him on the transfer market tomorrow, then we would have a whole host of top clubs in for him. Look at that vital stop he made for us in the first half against West Brom. It was a fantastic save.

"He was a huge presence for us at the back as far as helping our two young lads, Liam Ridgewell and especially Gary Cahill, come through. And, with the danger Birmingham pose from set-pieces, Thomas has a big part to play again this Sunday.

"He really makes his presence felt and does a lot of talking and, although he might make the odd mistake, he cuts out danger by leaving his line to make vital interceptions."

O'Leary even makes a comparison between Sorensen and the great Bruce Grobbelaar in his prime.

"Sure, Bruce used to miss the odd one, but he came and got 50 times more balls than he'd dropped. Just ask Alan Hansen and Mark Lawrenson what they thought about having him behind them and it's the same with Thomas. He's a reassuring presence."

Villa's goalkeeping coach, Eric Steele, is even more convinced that the level-headed Sorensen can cope admirably with the extra pressure of Sunday's biggest Midland derby day of all.

He says that proving his mettle at St Andrew's six months ago was a massive psychological lift - especially as he could so easily have sidestepped the game by pulling out through injury.

"That was a big day for Thomas," Steele said. "He had built himself up for what was such a big game for the club and then he went away with Denmark the week before and had to come off at half-time with a hamstring injury.

"It would have been the easiest thing in the world to have taken the easy option and missed the Blues game. But there was no way he was going to duck it and it was a huge thing for him in particular that he came out the other side with a win and a clean sheet. But I always knew he'd come through it, because he has the right 'mind-set'.

"He'd played in big derbies before he came to Villa and they don't come much bigger than saving a penalty from Alan Shearer for Sunderland at St James' Park. He was able to draw on that experience.

"There's a steel and resilience about him that says 'I've been through this'.

"He crossed a bridge at St Andrew's and doing the same thing again at Villa Park is just the next hurdle.

"It's all about strength of character and Thomas simply has the mentality of a No 1.

"You can be so close to the crowd at grounds like West Ham and Birmingham that, never mind worrying about someone shouting at you, you can actually hear them talking about you, but you just have to shut it out. Thomas is good at dismissing things, saying 'that game's finished, let's go on to the next one'.

"The main thing is being able to hold your hand up, admit 'I made the error' and move on, not by talking through it but by working through it. That's what Thomas did last season."