Ashley Young fired a deadly double as Manchester United gave their Premier League title push an important boost with a 3-1 victory at Tottenham.
Spurs' own title ambitions were left hanging by a thread after suffering a second successive defeat, despite dominating for large periods of the White Hart Lane clash.
Harry Redknapp's men had the better chances in the first half and nearly went ahead when Emmanuel Adebayor backheeled the ball into the net, but referee Martin Atkinson adjudged him to have handled in the build-up and the strike was disallowed.
United went ahead against the run of play on the stroke of half-time when Wayne Rooney got his head to Young's corner and the winger made it 2-0 after the break, volleying home from a tight angle after an error from Spurs defender Kyle Walker.
The England international then completed his brace in spectacular fashion in the 69th minute, curling home a stunner from 25 yards, and Spurs could only reply with a consolation strike when substitute Jermain Defoe netted late on.
The result leaves Spurs 13 points adrift of leaders Manchester City in the title race, while United remain two behind and unbeaten in seven.
This fixture has brought about many classics in the past, but Sunday's game started off slowly on a soggy afternoon in North London.
The absence of the suspended Scott Parker, injury victim Rafael van der Vaart and the ill Gareth Bale hit Spurs, although Sandro and youngster Jake Livermore did their best to deal with the imposing United midfield.
The visitors dominated the opening 15 minutes with Paul Scholes giving a master class in dictating the play in the middle of the park.
The Red Devils failed to fathom any chances, though, and Spurs soon started to take a grip on proceedings.
Aaron Lennon, recalled to the starting line-up after missing the past six games, rushed forward after cutting in from the flank before Jonny Evans put in a crucial block.
David De Gea nervously palmed away a shot from Adebayor, who burst forward after picking up Sandro's pass.
The crowd sensed a goal and Lennon continued to cause havoc down the right, whipping over a ball that ricocheted about the box. Tottenham suspected the ball had hit a United hand but Atkinson shook his head.
Younes Kaboul then fired a bullet of a free-kick that went just wide before Rooney ventured forward only at the other end only to be cut out by Ledley King.
Spurs poured forward looking for an opener and they thought they had it in the bag in the 38th minute.
Lennon snuck in to the box and Saha turned his cross straight at Adebayor, who backheeled the ball into the net.
However, he appeared to control the ball with his arm and referee Atkinson disallowed the goal.
The home contingent in the sell-out crowd vented their fury at Atkinson and their despair deepened on the stroke of half-time as United took the lead.
Sandro saw yellow for a late tackle on Young and the resulting free-kick saw Spurs concede a corner that led to United going ahead.
Young swung the ball in and Rooney found space in front of Kyle Walker to head home with Brad Friedel well beaten.
Spurs came out for the second half fired up. Livermore stung De Gea's palms with a fierce drive before Kaboul headed narrowly wide.
Benoit Assou-Ekotto skimmed the top of the bar with a wicked curling free-kick as Tottenham looked certain to equaliser.
The home crowd were stunned in to silence on the hour, however, as United added a second.
The Spurs defence switched off, allowing Nani to skip in to the box and fire a cross that ricocheted in to the path of Young, who adjusted his body to fire in a fine scissor kick.
Ferguson immediately brought on Ryan Giggs for Scholes and the travelling supporters mocked the home side by chanting "Harry for England".
United were starting to play some sublime football and their third came in the 68th minute in spectacular style.
Tottenham's defence backed off Young and he made them pay by unleashing a brilliant 30-yard strike that flew in over an outstretched Friedel.
More taunts came from the away fans as United threatened to go on the rampage.
Harry Redknapp brought on Niko Kranjcar, Danny Rose and Defoe to freshen things up and the move paid dividends to a minor extent when Defoe pulled back a consolation.
The former West Ham man picked up a wayward ball and advanced towards the United back line before belting home a 25-yard drive.
Spurs continued to push forward but two more goals in the three added minutes was too tall an order and United walked away with all three points.