Chimbonda had been impressive in defence for the home team until he deflected Louis Saha's strike into his own net two minutes into stoppage time.

Wigan, still stinging from their 4-0 League Cup Final defeat against United in Cardiff last month, looked on course for victory when Paul Scharner gave them the lead in the 60th minute.

But a Cristiano Ronaldo goal levelled for United and the visitors then stole victory seconds before the end of the game following Chimbonda's desperate intervention deep into stoppage time.

With Liverpool failing to stretch away from United in the race for second spot in recent weeks, this game was the perfect opportunity for Sir Alex Ferguson's team to leapfrog their rivals and strengthen their claims for the runners-up spot.

But United were awful in the first-half and Wigan created enough chances to leave the visitors trailing by a hefty margin at the interval.

Complacency may have been a factor on United's part having beaten Wigan by four goals on two occasions already this season.

However, Wigan were clearly stung by the manner of their Millennium Stadium defeat last month and they took their frustrations out on United with a dominant first-half display.

With Ruud van Nistelrooy starting on the bench again for United following his failure to make Cup Final starting line-up, Wigan had little to worry about defensively as they peppered Edwin van der Sar's goal in the opening period.

And the home side carved out at least six clear goalscoring chances, with United's midfield and defence in disarray, simply unable to cope with the pace and power of strike duo Henri Camara and Jason Roberts and the energy of midfielders Jimmy Bullard and Graham Kavanagh.

Irishman Kavanagh twice saw long-range efforts flash narrowly wide, while Bullard volleyed a Leighton Baines cross over the crossbar from 12 yards.

Roberts and Camara were the main threat, though, and the pair both saw good chances saved by van der Sar as United struggled to get a foothold in the game.

The worry for Wigan was that their missed chances would return to haunt them after the break and Wayne Rooney should have punished them within four minutes of the restart.

Gary Neville's cross teed up Rooney on the edge of the six yard box, but the England striker wastefully aimed a diving header high over the crossbar.

Wigan finally claimed the opener they deserved, however, when Scharner put them ahead on 59 minutes following a goalmouth scramble caused by Bullard's corner.

Arjan de Zeeuw's header had been cleared off the line by Ryan Giggs, but Roberts fired the rebound back towards goal, only for van der Sar to save and push the ball into Scharner's path, leaving the Austrian with a close range strike to score.

Ronaldo levelled in the 74th minute when he sidefooted van Nistelrooy's cross past Australian keeper John Filan.

That was barely deserved, but United still snatched the points when Chimbonda's attempt at a clearance from Saha's strike flew into his own net.