Villa striker John Carew believes the club made the right decision selling Zat Knight to Bolton this summer.

Solihull-born defender Knight comes up against Villa tomorrow for the first time since being offloaded to the Trotters in July for a move worth an initial £4million.

Striker Carew reckons the fine form of Knight’s replacements at the heart of the claret and blue defence, Richard Dunne and James Collins, means boss Martin O’Neill will have no regrets over his decision to sell the player.

But with the 6ft 6ins stopper sure to have a point to prove, Carew still expects a tough battle.

He said: “It’s a big game for him coming back to Villa Park. Zat is the tallest defender in the Premier League so it will be a big challenge in the air. He’s at least a couple of inches bigger than me.

“The players that have come in for him  in Dunne and Collins have done even better, so I guess it was the right decision for the team.

“But I’m happy for him that he’s playing in a team which can do things and he will be looking forward to the challenge.”

Carew has challenged the seventh-placed Villans to deliver a response from Wednesday’s last-gasp 2-1 defeat at West Ham after they spurned the chance to go fourth.

All three of Villa’s Premier League defeats this season have come against sides in the bottom half and Carew concedes their form has to improve against the lower-ranked teams – starting against 15th-placed Wanderers tomorrow.

He added: “We’re at home and we have to win.”