FRANK LAMPARD smashed in a late penalty to cap a riveting Chelsea comeback at Stamford Bridge.
Trailing to a Wayne Rooney rocket at the break, David Luiz struck a stunning volley and then Lamps took centre stage after Chris Smalling tripped sub Yuri Zhirkov with 10 minutes to go.
To make matters worse for United, Nemanja Vidic saw red for a second booking in injury time – the fourth time the Serbian had been sent off playing against Fernando Torres.
It means Arsenal can move within a point of United if they win their game in hand and fires the Blues back into the Champions League places.
The game got off to a rip-roaring opening and Torres had the ball in the net within a minute – a left foot volley being ruled out for a shove by Luiz.
It was the ball-playing Brazilian who then sparked a flowing move the length of the pitch which ended in a golden chance for Florent Malouda.
Ramires made ground down the right and found Nicolas Anelka. He pulled the ball back for his fellow Frenchman to sidefoot a controlled finish which lacked the conviction to beat and Edwin van der Sar.
There was no let-up to the pace. Javier Hernandez had a shot blocked by John Terry amidst cries for handball and Ashley Cole left Michael Carrick prostrate with a late challenge.
Michael Essien wriggled free on the edge of the area and saw a deflected shot drift wide, before Terry looped a header over from the resulting corner.
Chelsea were keen to keep the tempo high but Ramires took it a little too literally when he clattered into Carrick and was promptly cautioned by Martin Atkinson.
Much to the delight of the home fans, Rooney then got a free header horribly wrong from a Nani cross and saw the ball bounce clear off his shoulder. However, it was the England ace who was the one smiling minutes later.
Nani dribbled towards the edge of the box, slipped the ball to Rooney and, with the Blues defence backing off, he drilled the ball low past Petr Cech into the bottom left-hand corner.
On 40 minutes, Chelsea should have been level. Lampard’s free-kick was spilled by Van der Sar and Branislav Ivanovic latched on to the rebound just six yards from goal.
However, the ball rebounded too quickly for the Serb to finish cleanly, Van der Sar stuck up a big mitt and clawed it straight on to the chest of Nemanja Vidic, who somehow managed to angle it away to safety.
Vidic upended a charging Essien in the last minute of the half but Ashley Cole – who every time he touched the ball was invited to ‘SHOOT!’ by three-quarters of the stadium – could only curl his shot over.
Chelsea opened up the second period on the attack and another Lampard free-kick had to be fielded by Van der Sar, in what was proving to be one of his busier games of the season.
Luiz’s equaliser came on 54 minutes. Essien crossed for Ivanovic to flick on and as the ball bounced up 10 yards out the Brazilian hit a pinpoint volley that scorched into the corner with Van der Sar motionless.
Luiz’s follow through on the shot left Evra needing treatment, the Chelsea centre-half then sat Hernandez on his backside before finally being booked for upending Rooney from behind.
Didier Drogba entered the fray on the hour in place of Anelka.
Torres was wide with a strike as the home side continued their ascendency but it was still on a knife edge and Rooney had a great chance as he advanced on Cech from the left flank but fluffed his finish across goal.
With 20 minutes to go, Alex Ferguson opted for a double switch. Ryan Giggs came on for Paul Scholes and Dimitar Berbatov for Hernandez.
Carlo Ancelotti responded by introducing Yuri Zhirkov for Malouda as both sides still looked likely to snatch a winner.
Rooney had another shot beaten out by Cech before being tripped again by Luiz as the United bench screamed blue murder.
On 78 minutes the crucial moment. A Chelsea move looked to be breaking down in the box but Chris Smalling’s poor first touch allowed Zhirkov to bundle through and the young centre-half inadvertently tripped the Russian.
Ref Atkinson had no hesitation in pointing to the spot and Lampard confidently smashed the kick into the roof of the net.
Luiz was replaced by Jose Bosingwa to avoid a likely dismissal and the game was almost out of United’s grasp when Zhirkov’s shot was deflected on to a post by Vidic.
Sub Fabio was crowded out in the dying minutes before Vidic saw red for blocking the run of Ramires and receiving a second caution.
But Ancelotti’s side were on top at the end and merited the points after a stunning second half fightback.