West Ham kept their European hopes on track at Upton Park and blew a massive hole in Chelsea's chances of claiming second spot.

The Blues took the lead five minutes into the second half with Laurent Charvet's first ever goal for the club from Roberto Di Matteo's freekick.

But they were sunk by two goals in a frantic six minute spell as the Hammers kept their proud home record in tact and condemned the visitors to their fourth League defeat in five games under Gianluca Vialli.

Harry Redknapp's side have lost just once at home in the League this season and Trevor Sinclair and David Unsworth made sure it stayed that way with some clinical finishing.

Sinclair latched on to substitute Steve Potts' beautifully weighted through ball on 67 minutes to chip the advancing Dmitri Kharine.

And just six minutes later captain Unsworth drilled home a loose ball in the penalty area to give West Ham another priceless three points.

Chelsea made six changes from the side that had comprehensively outplayed Crystal Palace in midweek with player-manager Vialli not even naming himself among the substitutes.

Skipper Dennis Wise began his two-match ban but Mark Hughes returned after completing his suspension and was handed the captain's armband.

Roberto Di Matteo was also back in his midfield position although a revitalised Gianfranco Zola was dropped down too the bench.

West Ham manager Harry Redknapp was less expansive, making just two changes from the team that held champions' Manchester United to a 1-1 draw here in midweek.

Ian Bishop made a rare appearance in midfield for the injured Steve Lomas and David Unsworth was back in place of Steve Potts.

The Hammers managed the first shot on target in a quiet opening, Frank Lampard's freekick after Frank Leboeuf handled going straight to Kharine in the Chelsea goal.

Chelsea looked a shadow of the team that ran rings around Palace and created only two half-chances in the opening 45 minutes.

Tore Andre Flo's looping header threatened to wrong-foot Lama before the French international back-pedalled sharply to gather on his line.

And Lama had to be alert to race off his line on 24 minutes to save at the feet of Di Matteo, who had been sent clear by Eddie Newton following a mistake by Ian Pearce.

Just a minute later the home side manufactured the best chance of the period from skipper Unsworth's perfectly weighted cross-field ball.

Bishop timed his run well to meet it inside the area with a well-directed header but Kharine flung himself acrobatically to his right to pluck the ball cleanly from the air.

West Ham were forced to make a change at half-time when Impey, one of their best players in the opening period, had to go off with a groin injury to be replaced by Steve Potts.

That seemed to briefly unsettle the home side and Chelsea took the lead after 52 minutes with a well-worked freekick.

Di Matteo swung in a right-foot cross and Charvet rose superbly to power a header past the stranded Lama.

That sparked West Ham to life and they surged forward in search of the equaliser, Bishop blasting over with a half-volley from a corner.

It was not long before the home side were level however, as Sinclair scored his second goal in four days on 67 minutes.

The former QPR striker timed his run perfectly across the edge of the area and when Potts found him with a delightfully weighted pass, Sinclair provided the perfect finish with a delicate chip over the advancing Kharine.

The home side were now buzzing and just six minutes later were in front, skipper Unsworth leading from the front with his second goal for the club.

Bishop's low shot was deflected out to Unsworth at the back post and he drilled it home just inside the far post despite the attentions of several defenders.

Vialli saw the match slipping away and brought on Zola for Morris but it was West Ham that looked more like adding to the scoresheet.

Sinclair went close with a long-range effort and Leboeuf had to react quickly to stop Abou racing on to Berkovic's ball.

From then on it was a case of hanging on until the final whistle but for all their efforts Chelsea failed to trouble Lama unduly.

Teams:

West Ham: Lama, Ferdinand, Pearce, Unsworth, Lazaridis, Impey (Potts 46), Lampard, Berkovic, Bishop, Abou, Sinclair.

Subs Not Used: Forrest, Mean, Hodges, Coyne.

Booked: Unsworth.

Goals: Sinclair 69, Unsworth 75.

Chelsea: Kharine, Leboeuf, Hughes, Duberry, Di Matteo, Granville, Myers, Flo, Newton, Charvet, Morris (Zola 76).

Subs Not Used: Hitchcock, Clarke, Nicholls, Petrescu.

Booked: Charvet, Newton.

Goals: Charvet 54.

Att: 25,829

Ref: M J Bodenham (East Looe).