After Gloucester slipped 5-0 behind to a Mark Robinson try the boot of Walker and a drop goal from Lamb got Gloucester back in front. But it is with the ball in hand that Lamb is at his most destructive and he was involved at the start and the end of Gloucester's first try, for Lesley Vainikolo.
On halfway Lamb's delayed pass put prop Alasdair Dickinson in space and the loosehead made the most of his chance galloping 30 yards into Wasps territory. And once the ball was recycled Lamb was there to deliver a crossfield kick into the grateful hands of Vainikolo, for an 11-5 lead.
To Wasps credit they fought back well, with a side far less experienced than Gloucester's, and even pulled it back to 14-13, with a James Haskell try, before Lamb delivered the killer blow in the 47th minute.
Receiving the ball 40 metres out, Lamb cut open the Wasps defence with a long pass, Vainikolo again the grateful recipient and when two Wasps defenders were drawn to the giant wing, he slipped the ball inside for Walker to storm over unchallenged.
The Wasps coaches felt they match Gloucester up front (not sure they did in the lineout in the second half!) but couldn't match the Cherry and Whites invention with the ball in hand.
Gloucester Director of Rugby Dean Ryan said: "I am happy with that win. We lost in the last minute last year and it was almost set up for a repeat. "When you play Wasps, you want the result. Performances are there week in and week out but if you have a ding-dong against Wasps, you are happy to come out on top.
"This gives us a chance to push some resources at this competition in the later games. "We will look at this and think we let them back into the match but I'm pleased with the win."
Other Gloucester plays to catch the eye included David Young's feisty display at tighthead, against Tom French, and Alex Brown's magnificent second half display in the lineout. I counted three Wasps throws that he nicked in quick succession and forced Wasps into trying short throws, two of which resulted in free kicks.
The win stretched Gloucester's proud run in the competition. They have never lost a home game in the EDF Energy Cup, and it ensures Ryan will now target this competition and a trip to Twickenham.
Much of the post-match reaction from Wasps was dominated by Danny Cipriani, who dropped out of the 22 on the day, after feeling some soreness in his injured ankle. But McGeechan was able to reassure England fans that it was nothing more than a precaution and he would be fit for next weekend.
|Gloucester Rugby Score Card|
|London Wasps Score Card|