Premier League - United on verge of title after beating Chelsea
United put in a performance worthy of them winning a record 19th league crown as they made the defending champions look ordinary in their much-hyped title showdown to move six points clear at the top of the table with just two matches remaining.
Javier Hernandez gave Alex Ferguson's side the lead after just 36 seconds - the fastest goal of the season - when he pounced on David Luiz's error to meet Park Ji-sung's through ball and finish clinically past Petr Cech for his 13th league goal of the campaign.
Ryan Giggs had a hand in that opener, and the 37-year-old created the second for Nemanja Vidic midway through the first half when his cross was met by the Red Devils captain's stooping header from close range.
Frank Lampard pulled one back for Chelsea with 20 minutes remaining, but the Blues were not able to score the three goals needed to claim a comeback win which would have drawn them level on points with United.
Chelsea's record signing Fernando Torres was, as expected, consigned to the bench as Didier Drogba started up front, but the Ivorian was reduced to two efforts from free-kicks, one of which was beaten away by Edwin van der Sar and the other was fired wide.
United, by contrast, looked lethal every time they came forward, with Wayne Rooney having one well-struck effort from range parried by Cech and seeing another flash wide. Park also tested the Chelsea keeper from range while Hernandez missed to chance to double his tally when he failed to connect with Park's cross to the far post.
Chelsea boss Carlo Ancelotti made two changes at half-time, bringing on Alex in place of Luiz - something he had threatened to do immediately after the opening goal - as well as introducing Ramires for Jon Obi Mikel, while Ferguson used the break to replace John O'Shea for Jonny Evans.
Despite the Chelsea changes, United continued to control proceedings, and had two strong penalty claims turned down by referee Howard Webb.
First Antonio Valencia's chipped cross was clearly blocked by Lampard's arm, but World Cup final official Webb ruled it was not intentional, and the Rotherham referee ruled the same way when Valencia tripped over John Terry's outstretched leg midway through the second half.
Chelsea managed to claw a goal back when Ramires's cross was headed toward goal by Branislav Ivanovic and Lampard steered it past Van der Sar, but the two-goal deficit would have been restored moments later were it not for Alex's heroic goal-line block from Rooney's effort on the counter-attack.
Rooney had a strike deflected over the bar before Hernandez spurned two good opportunities to seal his first United hat-trick, but by then it was clear which side were the better, both in terms of the 90 minutes contested and the season as a whole.
Chelsea will prepare for matches at home to Newcastle and away to Everton in the vainest of hope that United will slip up, but fixtures for the leaders against Blackburn and Blackpool make it unlikely that the champions-elect will suffer two defeats.