Bolton's first-half scorers Matt Taylor and Kevin Davies
Two goals in as many first-half minutes gave Bolton victory over West Ham.
Matt Taylor gave them a dream start with a curling free-kick, followed instantly by Kevin Davies turning in Johan Elmander's cross to make it 2-0.
Mark Noble and David di Michele wasted clear chances and Carlton Cole saw a goal-bound header cleared off the line as West Ham tried to cut the deficit.
Their persistence was rewarded when Scott Parker scored from close range but an equaliser proved beyond them.
Taylor's opener was a delightfully curled effort over an unconvincing-looking defensive wall, after Jack Collison had conceded a free-kick in a central position.
The visitors had barely come to terms with going one goal down when the advantage was doubled, as Elmander's cross from the right fell perfectly into the path of Davies, who slid in between Jonathan Spector and Matthew Upson to shoot home.
A miserable passage of play for West Ham was capped by defender James Collins going off with a pulled hamstring, and, after this flurry of activity, the match fell into a rut as Bolton looked satisfied with their lead.
Towards the end of the half, the Hammers seized the initiative but failed to change the scoreline, despite several good chances.
First, Noble could have pulled one back when Cole's pass found him in the clear on the right, but he took the wrong option and tried to set up Collison when he would have been better going for goal himself.
Minutes later, another glorious chance was missed by the visitors as Di Michele shot wildly off-target, having run from the halfway line, and Taylor had to have his wits about him when he headed Cole's goal-bound header off the line.
Megson marvels at vital Bolton win
The early stages of the second half were increasingly ragged, with neither side really taking control and players from both sides putting in heavy challenges.
Apart from the ever-busy Taylor, Bolton looked satisfied with their lead, and West Ham's determination to change it was finally rewarded just after the hour mark, when Spector's low cross from the right went perfectly into the path of Parker, who stabbed home.
Gianfranco Zola's side sensed blood and went all out for the equaliser, and thought it was coming when Di Michele showed neat footwork in the box, but Gary Cahill's superbly timed block denied him what looked like a certain goal.
Bolton keeper Jaaskelainen did well to keep out Cole's bouncing header and would have been thankful for the lack of pace in Valon Behrami's shot as West Ham went all out in search of a late equaliser.
Kevin Davies had penalty appeals rejected late on when he was brought down by James Tomkins but the first half double-strike was enough to secure the points for Bolton.
Bolton manager Gary Megson:
"We seem incapable of going on to make it three or four goals after going 2-0 up. It happened against Blackburn and Spurs and again today.
"We showed apprehension but it would be wrong to criticise the players. We have won what I felt was a vital game for us - our biggest of the season.
"We got off to a great start but need to show more confidence and belief."
West Ham manager Gianfranco Zola:
"After all the chances we had I thought we'd get at least one point.
"They had two chances they took, we didn't - that's something we'll be working on in the next few days.
"Every moment in the game I had the idea that we were going to get something as the team were playing so well, they had problems handling us."
Jaaskelainen, Steinsson, Cahill, Puygrenier (Andrew O'Brien 73), Samuel, Kevin Davies, Mark Davies, McCann, Gardner, Taylor, Elmander (Muamba 76). Subs Not Used: Al Habsi, Smolarek, Makukula, Shittu, Basham.
Taylor 10, Kevin Davies 11.
Green, Spector (Sears 85), Collins (Tomkins 16), Upson, Ilunga, Behrami, Parker, Noble, Collison (Nsereko 62), Cole, Di Michele. Subs Not Used: Lastuvka, Lopez, Kovac, Tristan.
Steve Tanner (Somerset).
BBC Sport Player Rater man of the match:
Bolton's Matt Taylor 8.0 (on 90 minutes).
Please note that you can still give the players marks out of 10 on BBC Sport's Player Rater after the match has finished.
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