*Gabriel Agbonlahor’s third-minute goal booked Aston Villa’s place in the fourth round of the Carling Cup.* Agbonlahor back-heeled John Carew’s low near-post cross after Cardiff had clumsily lost possession in midfield. Gabor Gyepes and Joe Ledley headed just over for Cardiff, and Jay Bothroyd’s late effort was ruled out for offside. James Milner wasted a glorious chance to put the game to bed early in the second half when he hit the post from the penalty spot after Gyepes’s foul. For the second game in succession, there was no place for Nigel Reo-Coker in the Villa squad after a training-ground row with manager Martin O’Neil. Cardiff included three former Aston Villa players in their starting XI, and it was a mistake from one of those Villa old boys that led to the opening goal. Riccardo Scimeca was the culprit as his misplaced pass allowed Carew to race 40 yards down the right flank unchallenged before finding Agbonlahor at the near post. The striker’s first-time back-heel flick gave goalkeeper Peter Enckelman - another returning to his old stomping ground - no hope. Cardiff responded well as Gyepes and Joe Ledley headed just over in quick succession, while Gavin Rae’s deflected shot warmed Brad Guzan’s hands in the Villa goal. With Bothroyd used as a lone striker, the visitors made the most of the extra man in midfield and caused their hosts plenty of problems from free-kicks and crosses into the box. But the decisive touch was missing and the half ended with Stiliyan Petrov forcing Enckelman into his first save of note. Villa almost started the second half as they had the first, but Carew could not match his strike partner’s accuracy as he headed an inviting Milner cross wide. The visitors were then handed an even bigger let off on 58 minutes when Milner’s penalty hit the post after Petrov had been felled by Gyepes. Cardiff’s response was to send on top-scorer Michael Chopra from the bench. The change had little effect as the meanest defence in the Premier League stood firm to secure victory, but they were thankful for a marginal offside decision which denied Bothroyd and the need for extra time. *Aston Villa manager Martin O’Neill:* “I think that Cardiff were never out of it, and played some nice football, but we seemed to be in reasonable control, and I am delighted to have won and avoided another defeat in the competition. “Agbonlahor is on fire at the moment, he is playing brilliantly for us. He has got so much confidence now. “The goal he scored was maybe the sort he would not have attempted three-quarters of the way through last season, but he has so much confidence.”