Defender James Collins scored his first goal for Aston Villa to condemn Premier League leaders Chelsea to a second successive away defeat.• Ancelotti bemoans defendingMartin O'Neill's £5 million capture from West Ham took advantage of slack marking to head the winner after 52 minutes.Didier Drogba had given the Blues the lead after 15 minutes but Collins' defensive partner Richard Dunne levelled before the interval.Blues boss Carlo Ancelotti will be frustrated with his side's defending as two corners from Ashley Young presented Dunne and Collins with free far-post headers for the goals.It completely undermined the threat posed by his side going forward, with Deco shining in a free role behind the strikers.But Chelsea found Villa goalkeeper Brad Friedel in inspired form with a series of excellent saves making amends for gifting Drogba the opening goal.And Collins and Stephen Warnock also played their part in thwarting Chelsea with a series of excellent blocks.Skipper Stiliyan Petrov was effective in the centre of the park as Villa maintained their push for a European spot.The kick off was delayed for five minutes after referee Steve Bennett was taken ill and fourth official Keith Friend stepped into the breach.Villa striker Gabriel Agbonlahor had the first effort on goal and his shot on the turn was deflected wide.The home side had claims for a penalty rejected when Jose Boswinga wrestled with Agbonlahor in the box in attempting to get on the end of a first time cross from Petrov.James Milner then made a superb tackle inside his own box to deny Florent Malouda.But after 15 minutes a rare mistake by Friedel, in his 198th consecutive Premier League appearance, allowed Drogba to put Chelsea ahead.Drogba fired in a hopeful 30-yard drive but Friedel allowed the ball to bounce over his dive and into the corner of the net. It was Drogba's seventh goal of the campaign.Villa tried to retaliate and Chelsea skipper John Terry made a crucial interception to cut out a low centre from Milner with John Carew and Agbonlahor unmarked in the danger area.Chelsea were now looking the more likely to score and Ashley Cole was only just too high with a rising drive after a powerful surge forward.But after 32 minutes Dunne struck for the second successive match to bring Villa back on level terms.Essien was forced to concede a corner after good link up play between Agbonlahor and Petrov. Young's centre flicked off the head of Frank Lampard and Dunne was on hand to head home at the far past.The Republic of Ireland international celebrated in a way he had declined to do when netting against his former club Manchester City 12 days ago.Agbonlahor became the first player to be booked after 35 minutes for a challenge on Essien.Friedel redeemed himself for his earlier error when tipping over a chip from Deco at full stretch and then made another crucial stop to deny Drogba at point-blank range.Villa took the lead early in the second half when Collins was left completely unmarked at the far post to power a header past Cech from Young's inswinging corner.Lampard was only a couple of feet wide with a low 20-yard drive as Chelsea tried to respond, but Friedel showed he had fully recovered from his first-half error with another excellent block on a shot from Deco, who had been put clear by Drogba.Malouda was then denied by Friedel who beat out his fierce 20-yard shot as Chelsea searched for the equaliser.# Ancelotti bemoans defendingChelsea manager Carlo Ancelotti admits his team have work to do on set plays after they twice conceded from corners to go down 2-1 at Aston Villa.''We lost the game because we had two set plays,'' Ancelotti told Sky Sports. ''We need to be more focused on the situation. Chelsea played a good game and we don't want to lose the game in that situation, only if the other team play better than us. Aston Villa were very able on the set plays. We want to do better for sure. We need more concentration.''Villa manager Martin O'Neill insisted his team were good value for their victory. ''We can definitely compete,'' he said. ''We've a lot of good players in the team and it was a great effort against a top-quality team. My view is that anybody who finishes in front of Chelsea will win the Premier League.''Set pieces are part of the game today - World Cup finals have been settled on set pieces - but that tended to overlook what we can do. We try to get it wide and we've got players who can electrify the crowd.''O'Neill also claimed Villa should have had a penalty after Gabriel Agbonlahor went down in the box under pressure from Jose Bosingwa. ''I was a major decision,'' he said. ''I think when the referee sees it again he will admit that he got it wrong. It was a penalty and the consequence was that their player ought to have been sent off.''Former West Ham centre-back Collins, whose last goal was three-and-a-half years ago, was delighted to finally end his barren run.He said: ''It's something we've been working on. I haven't scored for a long time and it used to be a big part of my game. We've got some big lads in the team and it helps when the delivery is great from Ash (Ashley Young) and Milly (James Milner). This stands us in good stead. We know what level we're at and got to stay there week in, week out.''Richard Dunne added: ''We know we're a good side and we have the confidence. The manager tells us every day how good we are. The last performance here was really good, we want to be up there with the top four or top six.''Source: Soccernet.com