Frank Lampard rammed home a second-half penalty as Premier League champions Chelsea kept their title hopes alive by coming from behind to beat leaders Manchester United 2-1 in an absorbing encounter at Stamford Bridge.

England midfielder Lampard emphatically fired home from the spot 11 minutes from time to earn his team the points after substitute Yuri Zhirkov had fallen over Chris Smalling's outstretched leg.

The victory moves Chelsea to within 12 points of United, with a game in hand and a trip to Old Trafford to come later in the season, to leave the holders still dreaming of back-to-back crowns.

A high-octane contest in West London saw United head into half-time in front through a thumping low drive by Wayne Rooney, who had been cleared to play after escaping FA action for his elbow on James McCarthy in Saturday's win at Wigan Athletic.

United had largely been the better team in the first period, but Chelsea rallied after the interval and equalised on 54 minutes when January signing David Luiz volleyed home his first goal for the club.

Luiz was then fortunate not to pick up a second yellow card on 77 minutes for a trip on Rooney and, two minutes later, the Blues struck decisively when Zhirkov was felled by Smalling.

Zhirkov came close to a third goal as United struggled to respond and the visitors were reduced to 10 men in stoppage-time when Nemanja Vidic was shown a second yellow card for pulling back Ramires.

Vidic will now be suspended for Sunday's trip to arch-rivals Liverpool when United can ill-afford to lose in their quest for a record-breaking 19th top-flight title.

Annoyance

The annoyance for Sir Alex Ferguson would have been that Luiz appeared fortunate not to have been sent off for tripping Rooney moments before Lampard's winner, having already been booked.

Yet, that was only poetic justice given even the United boss felt his star striker was fortunate not to be banned for his elbow on McCarthy at the DW Stadium.

Until he found the net, the 25-year-old's notable involvement of a sustained purple patch for the visitors was to fluff a free header on the edge of the six-yard box.

Then he made the breakthrough. Allowed to creep away from the Chelsea defensive line by John Terry and the otherwise excellent Luiz, Rooney collected Nani's pass with his back to goal and spun round quickly.

Branislav Ivanovic recognised the danger but was powerless to do anything about it as Rooney took aim from 25 yards and beat Petr Cech with a ferocious shot that flew into the bottom corner.

At that stage, United deserved their lead.

Although Chelsea had plenty of possession and Ashley Cole was sarcastically urged to "shoot" by the visiting supporters, Florent Malouda had failed to capitalise on their one opening of note when he drilled a shot from Nicolas Anelka's cross straight at Van der Sar.

The Dutchman's moment of the season was still to come. And it will be talked about long after his retirement at the end of the season.

When he had only been able to push Lampard's long-range free-kick towards Ivanovic, the equaliser looked certain. In fairness to the Serb, the ball did not come towards him at the right height, so he could only bundle the ball rather than strike it.

Still, it was heading over the line until Van der Sar despairingly flung out an arm and somehow managed to push the ball upwards, changing its trajectory so it struck Vidic, who was scrambling back on the line.

Mission impossible

Van der Sar then completed mission impossible by clawing the ball away from goal, and dangerous Chelsea feet, so Darren Fletcher could hammer it to safety.

Luiz has thus far proved to be the most astute signing of Chelsea's £75million January purchases, combining solid defensive work with typical South American ability on the ball.

Clearly, he can strike a ball pretty well too as he proved when lashing home a 10-yard volley, from Michael Essien's cross.

Chances came and went with breathtaking regularity at either end. Lampard and substitute Didier Drogba for Chelsea. Rooney for United, drawing frustrated cries from Gary Neville, who was wedged amongst the visiting supporters, cheering for the club he has always loved.

Neville would have presumably taken a pretty dim view of Luiz's blatant trip on Rooney, which would surely have brought a red card had it been spotted by referee Martin Atkinson.

The Yorkshireman missed it, but not Smalling blocking off Zhirkov at the other end moments later, allowing Lampard to smash home his penalty.

Zhirkov came agonisingly close to grabbing a third goal when his fierce shot struck Vidic and crashed against the post.

Vidic's evening was to end on a sour note though to leave United hoping Rio Ferdinand will be fit to return from injury for the trip to Anfield.

Chelsea	Team Statistics	Manchester United
2	Goals	1
0	1st Half Goals	1
7	Shots on Target	2
8	Shots off Target	4
5	Blocked Shots	3
10	Corners	2
10	Fouls	14
1	Offsides	2
3	Yellow Cards	1
0	Red Cards	1
78.4	Passing Success	79.7
21	Tackles	22
66.7	Tackles Success	72.7
45.4	Possession	54.6
53.3	Territorial Advantage	46.7

Click Here for Official Teamsheet

Teams 

Chelsea  Cech, Ivanovic, Terry, David Luiz (Bosingwa 81), Cole, Essien, Ramires, Lampard, Anelka (Drogba 61), Torres, Malouda (Zhirkov 71)
Subs Not Used  Turnbull, McEachran, Mikel, Kalou
Booked  Ramires, David Luiz, Essien
Goals  David Luiz 54, Lampard (pen) 80

Manchester United  Van der Sar, O’Shea, Smalling, Vidic, Evra (Da Silva 81), Fletcher, Carrick, Scholes (Giggs 70), Nani, Hernandez (Berbatov 70), Rooney
Subs Not Used  Kuszczak, Brown, Rafael, Gibson
Booked  Vidic, Giggs
Sent Off  Vidic
Goals  Rooney 29

Attendance  41,825

Referee  M. Atkinson