Tom Homer landed seven penalties as London Irish ground out a Premiership win over Wasps to take them to third.
Nick Robinson twice kicked Wasps to a first-half lead but Homer proved more than his equal with the boot to make it 9-6 to the Exiles at the break.
Robinson converted a third attempt after the break to level but three unanswered kicks saw Irish pull away.
Wasps looked set to miss out on a bonus point before Christian Wade went in for a try at the death.
London Irish head coach Toby Booth:
"We had to do what was necessary. Four points is the greatest positive out of it.
"In a week's time no-one will even be talking about the game because there was not a great amount to talk about.
"It was win the territory battle, win the kicking game, dominate up front and keep your rewards. And that's how it panned out."
Wasps director of rugby Dai Young:
"It wasn't a great game. It was two teams who didn't have a great amount of threat with the ball and far too much aimless kicking from the sides.
"From our point of view, I thought Irish were more accurate in their kicking than we were. We talked about it all week that, if you are going to give Homer any penalties, then it is almost a guaranteed three points.
"He has kicked seven and we have lost two games now to two very good kickers. Newcastle were the same. We scored two tries there and still lost the game.
"Although we scored a try right at the end today, we had some clear-cut opportunities where our accuracy was just not good enough.
"There was a lack of concentration for us which is obviously disappointing. We had six opportunities where our inaccuracies saw us giving the ball back to Irish and they kicked us back into our 22.
"We have to have concentration for 100% of the game, not 75% of the game."
London Irish: Homer; Ojo, Ansbro, Spratt, Thompstone; Jarvis, Hodgson; Dermody, Buckland, Rautenbach; Kennedy, Garvey; Danaher, Gibson, Sinclair.
Replacements: Samson for Hodgson (66), Paice for Buckland (64), Corbisiero for Rautenbach (40).
Not Used: Lahiff, Sandford, Treviranus, Watson, G. Armitage.
London Wasps: Southwell; Varndell, Daly, Waldouck, Wade; N Robinson, Berry; Payne, Webber, Broster; Filipo, Wentzel; Birkett, Everard, Hart.
Replacements: Haughton for Southwell (70), Simpson for Berry (57), Taulafo for Payne (68), Lindsay for Webber (68), O'Donoghue for Filipo (18), Jones for O'Donoghue (72).
Not Used:Baker, Davis.
Ref: Sean Davey (RFU).