Arsenal 2 West Ham 0

Alessandro Diamanti missed a penalty in the last minute of the first half, awarded when Thomas Vermaelen brought down Guillermo Franco as he headed towards goal.

It earned the Belgian defender a red card but Manuel Almunia made a good save from Diamanti's kick.

Arsenal then reorganised for the second half, making it difficult for West Ham to play around them, but in truth the Irons looked short of ideas and inspiration and ultimately didn't really deserve anything from the game.

Gianfranco Zola made several changes from the side that lost 4-1 at Chelsea last week, with Scott Parker, Danny Gabbidon and Kieron Dyer all absent.

But he chose a more attacking formation than at Stamford Bridge, pairing Mido and Guillermo Franco up front, with Alessandro Diamanti lurking just behind them.

The Irons started brightly, for the first five minutes at least, until they allowed Denilson all the time in the world to put Arsenal ahead.

Matthew Upson's weak defensive header fell to the Brazilian lurking outside the box and he played a clever one-two with Bendtner before driving a low shot past Rob Green from 18 yards.

Given West Ham's poor away form this season - with their only win coming at Wolves on the opening day - there were fears this could end up as a heavy defeat.

But Zola's men got stuck into the Gunners and made a game of it, although there was always the sense that Arsenal could step up a gear or two if needed.

Diamanti went close for the visitors when he put a free kick just over the bar, while Bendtner saw a shot flash past Green's post.

Mido then failed to connect with a Junior Stanislas cross as he bore down on goal, but it was still Arsenal who were playing the better football.

They almost doubled their lead when Daprela headed a Clichy cross out for a corner as Nasri was set to head the ball home.

West Ham were then presented with their chance to equalise, thanks to Vermaelen's indiscretion, but they failed to capitalise.

The second period saw heavy rain saturate the Emirates pitch, making conditions greasy underfoot, but that cannot excuse too many West Ham players failing to make a significant contribution.

Junior Stanislas, whose pace would surely have troubled a tiring Arsenal defence, too often found himself a peripheral figure, while Diamanti - perhaps upset by his penalty miss - seemed more intent on showing his petulant side rather than his skilful one.

Even the introduction of Carlton Cole failed to spark the Irons, with his best effort skimming the post. He was well shackled by Sol Campbell.

Arsenal duly wrapped up the points when Cesc Fabregas converted an 83rd minute penalty awarded against Matthew Upson for handball.

Zola felt his side missed a good opportunity to earn at least a point.

He said: "It feels that way, especially after the first half, which I thought was probably the best performance of the season.

"We missed the penalty but in the second half we should have done better. We lost our composure.We did well in the first 45 minutes when we moved the ball around but then we became impatient, lost shape and energy and in the end we conceded another goal.

"If we are able to produce that first 45 minute performance for 90 minutes today would have been a different result."

Unfortunately for Zola, the result wasn't different and it leaves the Hammers perilously close to the Premier League drop zone, making tomorrow night's clash with Wolves at Upton Park all the more crucial.

Arsenal: Almunia, Vermaelen, Song, Campbell, Clichy, Nasri (Sagna, 75), Denilson, Eboue, Fabregas, Arshavin (Eduardo, 84), Bendtner (Diaby, 58). Unused subs: Fabinaski, Silvestre, Walcott, Rosicky.

Booked: Campbell

Sent off: Vermaelen

Goals: Denilson 5, Fabregas 83 (pen)

West Ham: Green, Spector, Daprela, Upson, Tomkins, Kovac (Noble, 70), Behrami, Stanislas, Diamanti, Mido (McCarthy, 75), Franco (Cole, 57). Unused subs: Stech, Ilan, Ilunga, Spence.

Booked: Kovac, Diamanti, Upson, Daprela.

Attendance: 60,077

Referee: Martin Atkinson