Manchester United capitalised on the exit of Paul Robinson to maintain their Premiership pursuit of Chelsea.

Paul Scholes and Rio Ferdinand put the hosts on top before Ruud van Nistelrooy wrapped up victory with his 16th goal of another prolific campaign just after the hour mark.

But the result might have been different had it not been for the sickening collision between Robinson and Thomas Gaardsoe, which led to the excellent Baggies defender being carried off the pitch with what appeared to be a severe neck injury.

Within a minute, Scholes had belted home from the edge of the box, setting United on course for their seventh win in eight Premiership outings, a run which has remarkably brought them just a single point closer to Jose Mourinho's men.

The result also kept West Brom firmly in the relegation mire, although for Baggies boss Bryan Robson it was a case of what might have been.

Robson has never been viewed as a master tactician but, after taking the warm applause of the home supporters who have never forgotten his contribution to the Red Devils cause, he promptly came up with a move which threatened to derail any lingering title drive.

Robinson has been performing so well for the Baggies recently there have been strong noises from the Black Country urging Sven-Goran Eriksson to draft him into his England World Cup squad.

His club manager clearly felt he was up to the task of snuffing out the threat of Wayne Rooney and the man-marking move worked like a dream until the full-back crashed into Gaardsoe just before the half-hour mark.

West Brom's irate supporters quickly noticed it was Rooney who had pushed Robinson into his team-mate but, while the incident did bring the visitors a free-kick, the England man could not be blamed for the accidental consequences of his actions.

It was immediately obvious the damage was serious. West Brom medical staff took a full five minutes just to get Robinson on to a stretcher and he left the field to a standing ovation.

He probably had not even reached the visitors dressing room before United went in front.

After spending so long as a non-existent attacking threat, Ferdinand has suddenly emerged into a danger man.

It was the England man who set up the hosts opener, surging into the West Brom box before cutting a pass back to Park Ji-sung.

The Korean appeared to be being tugged back by Steve Watson but managed to keep his balance long enough to prod the ball into Scholes' path and the former England man quickly drilled home his third goal of the season.

Amazingly, after taking 140 games to open his account, Ferdinand is now only one behind Scholes in this season's standings.

The game was into the sixth minute of stoppage time added on for Robinson's treatment when Ryan Giggs floated a corner to the edge of West Brom's six-yard area.

There was some serious miscommunication in the visitors' defence as Ferdinand's near-post run went unchallenged and then neither Gaardsoe nor keeper Tomasz Kuszczak were able to prevent the angled header finding the net.

It was tough luck on the visitors, who, with one notable exception, had restricted their hosts to half chances prior to Robinson's exit.

That opportunity came after just four minutes when Gary Neville curled a superb cross over from the right flank straight on to Scholes' head.

Given the midfielder had called for United to restore their habit of killing teams off early, it was ironic he should nod over from four yards when he was completely unmarked.

For a long time afterwards, it appeared the Red Devils would pay for Scholes' blunder. Unfortunately for Robson and his team, Robinson's injury changed the game.

While Ferdinand's conversion to sharp-shooter is a relatively new phenomenon, Van Nistelrooy has now been finding the net on a regular basis for the past five seasons and the Dutchman arrived on cue to nod home Park's excellent cross just past the hour mark.

It was a goal which allowed Ferguson the luxury of giving Van Nistelrooy a rest at the start of a congested schedule, along with Scholes, who had departed the action a few moments before.

Teams

Man Utd Van der Sar, Neville, Ferdinand, Brown (Richardson 45), O'Shea, Park, Fletcher, Scholes (Smith 61), Giggs, Rooney, van Nistelrooy (Saha 66).

Subs Not Used: Howard, Bardsley.

Booked: O'Shea.

Goals: Scholes 35, Ferdinand 45, van Nistelrooy 63.

West Brom Kuszczak, Albrechtsen, Curtis Davies, Gaardsoe (Gera 67), Robinson (Kamara 32), Watson, Chaplow, Wallwork, Carter, Greening, Ellington (Campbell 61).

Subs Not Used: Horsfield, Kirkland.

Att: 67,972

Ref: M Clattenburg (Co Durham).