LONDON (AFP) Manchester United closed the gap on Premier League leaders Chelsea as the champions swept to an impressive 3-1 win against title rivals Arsenal on Sunday. Sir Alex Fergusons side stunned the Gunners with two goals in four minutes in the first half at the Emirates Stadium and were never in danger of surrendering their lead. Arsenal goalkeeper Manuel Almunia pushed Nanis cross into his own net before Wayne Rooney put the champions in complete control with his 100th Premier League goal. South Korea winger Park Ji-Sung added Uniteds third goal in the second half to ensure Fergusons men moved within one point of Chelsea thanks to their most emphatic performance of the season. England star Rooney demonstrated the predatory instincts that make him, on current form, the most lethal forward in the world, but it was Portugal winger Nani, revitalised in recent weeks, who stole the show with a superb display. Arsenal, beaten for the first time in 11 league games, had no answer to either player and, although Thomas Vermaelen got one back late on, Arsene Wengers team looked short of the resilience and cutting edge needed to win the title. Ferguson, who was without defensive duo Rio Ferdinand and Nemanja Vidic, selected Nani ahead of in-form Antonio Valencia and Ryan Giggs and it proved an inspired decision. With Chelseas victory at Burnley on Saturday moving the leaders four points clear of United and five ahead of Arsenal, both teams knew a defeat could be disastrous to their title hopes. Arsenals Andrey Arshavin was a thorn in Uniteds side in the early stages and the Russian twice threatened to open the scoring. He curled a shot wide of Edwin van der Sars far post, then went closer when he teased Wes Brown before tricking his way past the United defender and shooting narrowly wide. Nani, playing on the right flank instead of his usual left wing berth, led Uniteds response in imperious fashion. He was causing Gael Clichy problems with his pace and nearly scored with a close-range shot after a goalmouth scramble. Clichy had been warned but the French left-back had no answer to Nani again in the 33rd minute. Faced with Clichy and Samir Nasri on the touchline, Nani cleverly flicked the ball past both opponents and surged into the penalty area. Denilson couldnt stop Nani either and the United star was able to loft a cross goalwards. Almunia had a chance to tip it over, but mistimed his attempted save and could only push the ball into his own net. Arsenal were rocked by Almunias mistake and, just as in Uniteds Champions League semi-final victory over the Gunners last season, Fergusons team were able to take full advantage on the counter-attack. Back in May it was Cristiano Ronaldo administering the killer blow, this time it was Rooney who capped a stunning break in the 37th minute. When Park cleared to Rooney from inside his own penalty area, there was no immediate sign of danger. But in an instant Rooney had passed possession onto Nani, who sprinted towards the Arsenal box. Rooney had continued his run and the England forward met Nanis precise pass with a first-time shot that gave Almunia no chance. It was a sublime finish to a breath-taking move and Ferguson and his staff rose as one to acclaim Rooneys 22nd goal of the season. United had failed to win any of their last six away games against 'big four rivals, but this one was in the bag just after half-time. Rooney served notice that United werent going to settle for two goals with an audacious effort that Almunia scrambled to save, but it was Park who put the result beyond doubt in the 52nd minute. Running onto Michael Carricks chipped pass, Park was able to break into the penalty area without a single Arsenal player making a challenge and the South Korean was still unopposed as he slotted a low shot past Almunia at his near-post. Belgian defender Vermaelen reduced the deficit in the 80th minute when his acrobatic volley from the edge of the area deflected in off Brown.