Manchester United 0-1 Chelsea: Mata strikes late Chelsea took a mighty stride towards a place in next season's Champions League as Juan Mata's deflected late winner earned victory over ten-man Manchester United. Scorer: Chelsea - Mata (87) The drabbest of affairs seemed certain to end in a goalless stalemate until Mata's shot flicked off Phil Jones and crept in at the far post. United thought they should have had a free kick earlier in the move and their frustrations boiled over as Rafael was sent off in the final minute for chopping down David Luiz. The result means victory for Chelsea against Tottenham at Stamford Bridge on Wednesday will seal a top-four spot thanks to their superior goal difference. United manager Sir Alex Ferguson, while having no complaint about the result, expressed disappointment with the performance of referee Howard Webb, believing that Rafael's dismissal came after he had been provoked by his fellow Brazilian. He retaliates, the player who retaliates always gets the bigger penalty. He [Luiz] has elbowed him twice, but he [Rafael] should know better," he said. The referee hasn't even seen it and has gone with the fact that Luiz rolled about and that's convinced him it's a red card. We weren't getting anything out of the referee anyway. I can't make any excuses for a terrible performance. They surrounded the referee all day and I think that affected the referee. Chelsea boss Rafael Benitez refused to discuss the incident, saying he did not see what happened and was keen to look forward to Wednesday's encounter. "I didn't see the incident or replays," he said. I try to enjoy when we win, it's a situation you can see 20 times on TV, but it won't change anything. For us every game is massive now. Playing against the champions was tough and we did very well . We have to beat Tottenham. It will not be easy. Chelsea's victory was just about deserved, although the game will not live long in the memory. Although Ferguson insisted there would be no slackening off even though the title was won a fortnight ago, it was hard not to notice a change in attitude by the hosts. With Michael Carrick missing, they looked to Ryan Giggs for some incisive passing and it took the veteran Welshman some time to find his range. However, both Rafael and Jones burst into the box, only for Chealsea goalkeeper Petr Cech's massive frame to get in the way. On the latter occasion, the ball broke to Tom Cleverley, who blazed over, just as Antonio Valencia had done in the opening stages. Giggs eventually lofted a superb pass over the Chelsea defence for Robin van Persie to run onto. The free-scoring Dutchman simply helped the ball on, only to nudge it wide. Just before half-time, Giggs presented Van Persie with a better opportunity when he crossed from the left, only for Cech to again get in the way. Meanwhile, Chelsea rarely threatened United keeper Anders Lindegaard, who had been handed his first Premier League start since December. Demba Ba put a couple of chances over, as did Victor Moses. The nearest Chelsea went in the opening period was when Oscar was afforded far too much room to run at the United defence before sneaking a shot at goal with the outside of his right foot which Lindegaard did well to push on to the post. The deadlock should have been broken 15 minutes from time when Frank Lampard picked out Mata with a sublime chip into the box. But, unmarked, the Spain midfielder inexplicably failed to make any contact with his header and Rafael bundled the ball away. Branislav Ivanovic then needed to make an important intervention to prevent Rafael's low cross reaching Van Persie at the other end before Luiz sent a free-kick wide. It was all rather humdrum until the final five minutes. Rooney felt Ramires had fouled him on the edge of the Chelsea area to win possession in the first place, but once they countered, the visitors always had an extra man. The ball was eventually ferried out to Mata, whose shot may have been creeping in, but definitely did after it flicked off Jones, bouncing in off the post. United's frustrations boiled over almost immediately as Rafael went through the back of Luiz by the corner flag, believing the Brazilian to have swung an elbow. Giggs was incensed at Oscar for waving an imaginary card but, after the two sides had been separated, referee Howard Webb did just that, a red one that will mean a three-match ban and an early end to Rafael's season. Cech hailed Mata's goal as "massive" as they moved into third place in the Barclays Premier League. The Blues are now a point clear of Arsenal and three in front of Tottenham as they head for Wednesday night's clash. "It was a massive moment," said Cech. After the results yesterday [both Arsenal and Tottenham won], we knew that we had to win. We have a massive game and we go into the game three ahead - if we win we leave them behind. It changed the preparation for Wednesday. Manchester United: Lindegaard,Da Silva,Evans,Vidic,Evra,Jones, Anderson (Rooney 69),Cleverley (Buttner 68), Valencia (Hernandez 90),van Persie,Giggs. Subs Not Used: De Gea,Ferdinand,Scholes,Kagawa. . Chelsea: Cech,Azpilicueta,Ivanovic,Luiz,Cole,Ramires,Lampard, Oscar,Mata (Ake 90),Moses (Torres 76),Ba. Subs Not Used: Turnbull,Ferreira,Cahill,Terry,Benayoun.