This was always supposed to be a one-sided game; the only surprise was the identity of the one side. West Ham had not conceded here for four games, yet their defence was chaotic. Bolton had not scored away for four games, yet they attacked with brio and, on occasion, brilliance. "We have some terrific players at this football club," Owen Coyle said, grinning. "They've just got to trust themselves."

Bolton's regret is that they had only a two-goal lead by the time Tamir Cohen received his second yellow card with 20 minutes remaining. So it was that after Alessandro Diamanti gave the home side hope by cutting in from the right wing two minutes from time and shooting inside the far post, the visitors came within a couple of inches of throwing victory away.

In the 94th minute, the West Ham substitute Junior Stanislas chested the ball down on the edge of the area and volleyed against the meat of the bar with the goalkeeper emphatically beaten. He might have cursed his luck, but a draw would have been a travesty. "They were better than us," Gianfranco Zola said. "I've got no complaints."

In the first half, Bolton fair blew the home side away with an unrelenting, irresistible barrage of pressure. They scored twice inside the first 16 minutes and still were not sated, creating chances with a regularity that had the home fans howling with frustration and rage. Had they been four up by half-time, West Ham could hardly have complained. On this evidence, Coyle has not so much transformed Bolton as supercharged them.

Purists may still mutter about their style of play, but Bolton could hardly be accused of a lack of quality. It always helps, though, to be playing against a defence as apparently hapless as the Hammers'. Their left-back, Jonathan Spector, and centre-half, James Tomkins, will look back on this match with a shudder of horror. Both of Bolton's goals came from their right flank, where Lee Chung-yong was ascendant throughout. In the 10th minute he took on Spector, sent in a cross which curled in towards the far post and Kevin Davies thundered in to head past Robert Green.

Six minutes later, Gretar Steinsson chipped a ball into the inside-right channel, Tomkins attempted to usher it out of play and Davies stole in to poke it towards the centre. To their credit, two Bolton players had ventured into the penalty area, gambling on the possibility of their captain winning the ball. One of them, Tamir Cohen, headed down and the other, Jack Wilshere, volleyed into the net.

Chances continued to come, Johan Elmander guilty of a particularly glaring miss from Davies's cross in first-half stoppage time. Carlton Cole, meanwhile, had West Ham's best opportunity of the first half but delayed his shot and the excellent Sam Ricketts stole the ball off his toe. Bolton could not quite keep up that level of intensity but, though they threw on attacking players, West Ham still could not attack with conviction.

Victory took Bolton above their opponents, and they visit Sunderland on Tuesday in search of a third successive win. "Psychologically, we're on the up," Coyle said. West Ham, meanwhile, are looking down once more, and next visit Chelsea and then Arsenal. "I don't think many people were expecting Bolton to beat us today," Zola said. "In football, you never know."

THE FANS' PLAYER RATINGS AND VERDICT

Hamish MacKay, Over Land and Sea Bolton came down and did a job on us, as they usually do. Davies had a storming performance. But we gave away two soft goals in the first 15 minutes, both through poor defending, and when you're 2-0 down against Bolton it's never going to be easy. We never got going and we didn't look like scoring until the last 10 minutes. Stanislas hit the bar right at the end so we could have got a point, but we didn't deserve it. If we're going to stay up we need to win our home games. If we defend at Stamford Bridge and the Emirates like we did today, we'll get hammered, so hopefully it's a wake-up call for the players that they have to concentrate for the whole game.

The fan's player ratings Green 6; Faubert 5 (Dyer 47 4), Tomkins 4, Upson 5, Spector 6; Behrami 6, Kovac 5 (Stanislas 75 6), Parker 6, Diamanti 7; Franco 4 (Mido 67 5), Cole 5

Shaun O'Gara, Supporters' club Coyle's first away win, Wilshere's first goal, back-to-back wins... it's a day of firsts. We deserved it. We played really well, passing the ball much better than we have for some time. Davies gave them a torrid time, and when we went down to 10 men, we defended really well and showed great spirit. The ref seemed intent on helping West ham as much as he could by booking Bolton players. Coyle is trying to get us playing a more passing style, and that will take time. But there are signs of it already. Knight and Muamba have improved and the players he's brought in – Wilshere and Holden – are passers. Wilshere particularly looks a fine young player.

The fan's player ratings Jaaskelainen 7; Steinsson 7, Knight 8, Ricketts 8, Robinson 7; Lee 7, Muamba 7, Cohen 6, Wilshere 7 (Taylor 78 6); Davies 9, Elmander 7 (Gardner 74 7)

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