The Dutchman equalises in added time to deny the Hammers in the FA Cup third round after James Collins' double had put them on the brink of an historic victory
Substitute Van Persie lashed a superb right-footed finish into the bottom corner in added time to force a replay at Old Trafford just when the Hammers looked to have booked their place in Sunday’s fourth round draw.
Tom Cleverley swept United ahead in the 23rd minute but Welsh defender James Collins responded with two almost identical headers, both from crosses delivered by Joe Cole on his return to his boyhood club.
Van Persie’s goal was his 20th of the season in all competitions for United and the Dutchman revelled in the celebrations in front of United’s 5,000 travelling fans after once again saving Sir Alex Ferguson’s side.
West Ham boss Sam Allardyce certainly will have been pleased with the impact made by Joe Cole, who went straight into the West Ham starting line-up after re-joining the Hammers from Liverpool during the week, while United rested Van Persie as Chicharito and Danny Welbeck were paired in attack.
The flavour of the occasion was set by the presence of David Beckham in the stands while rapper Lethal Bizzle performed on stage before kick-off as the Hammers looked to make best use of their home advantage.
It may have fired up the home crowd but the home players started the game at pedestrian pace as United - and Paul Scholes in particular - dominated the early exchanges, playing with slick passing and movement.
West Ham almost broke the deadlock in the 12th minute but Alou Diarra’s header from a corner was cleared off the line by Scholes, before West Ham youngster Daniel Potts made a similar clearance to deny Nemanja Vidic at the other end.
In the 23rd minute, United scored the goal their play deserved and it was in keeping with their start to the game. Rafael and Chicharito linked up well before the Mexican squared for Cleverley to sweep a lovely finish into the top corner from 10 yards.
The midfielder’s strike appeared to finally wake up the West Ham players and out of nowhere the hosts drew level four minutes later. Collecting the ball on the left, Joe Cole whipped in a vicious cross and Collins timed his run perfectly to rise high and glance his header into the far corner.
West Ham’s most likely route to goal always looked to be from a set-piece or a cross and they took the lead in the 59th minute with an almost exact copy of the opener. United failed to put any pressure on Joe Cole, who swung in a superb delivery that Collins powerfully headed into the far corner after getting in front of Nemanja Vidic.
United responded by bringing on Van Persie as they piled the pressure on West Ham, but the hosts appeared to be standing firm as the atmosphere reached fever pitch.
Then, as the clock ticked into added time, Giggs played a marvelous pass to Van Persie, who took it brilliantly in his stride and lashed into the bottom corner.