A classy try from Josh Lewsey was the highlight as Wasps ground out a victory over London Irish to move top of the Guinness Premiership - at least for one night.

Lewsey's score just before half-time was a rare classy moment in a poor game dominated by penalties and the whistle of referee Sean Davey.

Alex King booted 12 points and Jeremy Staunton a further six as Wasps, who beat Saracens at Twickenham last Saturday, earned their second London derby win in successive weekends.

The Exiles secured a bonus point with a try from Topsy Ojo and 12 points from the boot of fly-half Riki Flutey.

But for two teams who pride themselves on playing attacking rugby, especially in such fine conditions, it was a poor show at Adams Park.

Both sides were forced into late changes with key playmakers Dave Walder and Mike Catt both dropping out on the morning of the game.

London Irish were in complete control of the lineout, stealing Wasps' ball seemingly at will, but it took them 25 minutes to turn that pressure into points.

By then Wasps led 9-0 from three King penalties after assuming an early dominance in the scrum.

The first scrummage of the game was re-set four times before referee Davey finally penalised the Exiles and King slotted the simple penalty from straight in front of the posts.

King followed that with two more in quick succession after London Irish hooker Danie Coetzee had been sin-binned for diving over the top of a ruck.

Despite being a man short London Irish began to find their feet and only the bounce of the ball denied Ojo a try after Delon Armitage's neat chip over Lewsey.

Wasps held firm as the Exiles tried to drive their way over but London Irish eventually worked an opening after securing their fourth lineout steal of the match.

Flutey picked out Ojo in space on the right wing with a perfect cross-field kick and the London Irish winger simply had to catch the ball and fall over the line.

London Irish number eight Juan Leguizamon began to cause Wasps some serious damage but a poor pass from Armitage to Ojo's feet cost them a clear try-scoring opportunity.

Flutey slotted a well-struck drop-goal from 35 yards to bring London Irish back to within a point but it lasted barely two minutes before Lewsey, playing on the left wing, produced a touch of class.

The England international gathered a bouncing ball, chipped expertly around Armitage and beat the full-back to score in the corner.

King missed his third successive kick just after the break before the game sprung to life.

Lewsey embarked on a dashing run from deep only to lose possession in the tackle. Wasps held firm as the Exiles counter-attacked and then pushed down field.

Lewsey was tackled into touch superbly by Shane Geraghty as he reached for the try-line but play was called back for a London Irish offside and King found his radar to boot Wasps 17-8 ahead.

The bright spell soon died out as the game descended into a kicking duel between Flutey and Jeremy Staunton, who replaced King at fly-half.

Flutey struck two in return to drag London Irish within three points before Staunton landed one from 40 metres, the very edge of his range.

Rob Hoadley was penalised for killing the ball but London Irish could not take advantage and Staunton kicked Wasps two scores clear with a neat drop goal seven minutes from time.

The Exiles earned their bonus point with Flutey's third successful penalty.