Nani scored the only goal as Manchester United overcame Sunderland to ensure the Premier League title race will go down to the final day of the season. With leaders Chelsea beating Liverpool earlier in the day to go four points clear, United knew they had to win. Nani drilled them ahead before Dimitar Berbatov missed two chances and headed a third onto the bar, while a Michael Carrick shot was cleared off the line. Sunderland threatened sporadically but United held firm for an imperative win. It keeps them a point behind Chelsea ahead of the last round of matches next Sunday. The Blues will clinch the title if they beat Wigan at Stamford Bridge, while United must get the better of Stoke and hope Carlo Ancelotti's men fail to pick up all three points. United kicked off knowing that nothing other than a victory would suffice if they were to keep alive their hopes of an unprecedented fourth straight Premier League title. Buoyed by recent victories over Manchester City and Tottenham, they made an assured start and went close inside five minutes when the fit-again Wayne Rooney saw a drive parried by Craig Gordon and Ryan Giggs' follow-up was deflected to safety by Phil Bardsley. United, unbeaten against Sunderland in the league since March 1997, were dominating possession and producing a slick brand of pass-and-move football that the hosts struggled to keep pace with. But in losing only two of their previous 16 home home league games, the Black Cats have proved what a force they can be at the Stadium of Light and gradually they came into the game. They stopped affording Paul Scholes and Giggs time and space in midfield and then began to push forward themselves, John Mensah and Lorik Cana both heading wide from promising positions. The game was flowing from end to end and a sumptuous Giggs drive skimmed the angle of post and bar before United keeper Edwin van der Sar tipped over a fizzing drive from Steed Malbranque. It was easy to see why United are holders of the best defensive record in the league as a back five of Van der Sar, John O'Shea, Jonny Evans, Nemanja Vidic and Patrice Evra rebuffed everything that was thrown at them. But the principle difference between the sides was quality in the final third, illustrated to devastating effect as United opened the scoring. Giggs, Berbatov, Rooney and Darren Fletcher combined to feed Nani and the Portuguese winger curved a rasping finish across goal and into the bottom corner with the outside of his right foot. United were stirring and a Giggs cross was almost put into his own net by Michael Turner before Evra had a shot saved and Rooney released Berbatov, only for the Bulgarian to skew wide. Unfortunately for Sunderland, boss Steve Bruce was forced into making two first-half substitutions after Mensah limped off and David Meyler suffered a serious-looking leg injury following a challenge with Evra. United boss Sir Alex Ferguson would have been frustrated at his side's inability to add to their advantage before the break and they came out for the second period as if desperate to put the game to bed as quickly as possible. A Fletcher backheel sent Nani through but his dinked effort was saved by Gordon and Berbatov wasted another gilt-edged opportunity by volleying over from Rooney's cross. Rooney again found his strike-partner with a pinpoint centre but this time Berbatov's goalbound header ricocheted off the head of Kieran Richardson and onto the bar. Sunderland eventually began to assert themselves and half chances came and went, Bardsley earning a caution for unnecessarily falling to the ground after he had burst past Giggs into the box. It seemed United, who have now gone five away games without conceding, could up the intensity almost at will and after Rooney lashed just wide substitute Carrick was denied by Turner's goal-line clearance. The reigning champions came under pressure late on but, aided by substitute Rio Ferdinand's return from injury and Owen Hargreaves' first appearance since September 2008, they would not be breached. Source: BBC