Wasps inflicted a second successive Premiership defeat on Saracens by claiming a 26-20 win.
Sam Spink’s try and four Jimmy Gopperth penalties helped Wasps build a 19-13 lead over their high-flying visitors.
But, as Sarries pushed, lock Elliott Stooke sealed victory with a late converted try on the break.
Alex Lewington and Tom Woolstencroft scored first-half tries for Sarries while Nick Tompkins crossed seconds from time to earn a losing bonus point.
Returning at lock after nine months out with a knee injury, club captain Joe Launchbury made an immediate impact, setting up Spink to give Wasps a 10-point lead in the seventh minute.
Lewington thought he had pulled a try back after 24 minutes only to fail to ground the ball.
But the winger did cross five minutes later before a Woolstencroft try on the stroke of half-time levelled the fixture for Saracens at the break.
In front of a boisterous home support, Wasps dominated after the restart with two Gopperth penalties to add to his two first-half efforts, giving them a 19-13 lead at the hour-mark.
In the 63rd minute Andy Christie thought he had added five points for the visitors only for his try to be disallowed after the Television Match Official discovered Tim Swinson had cleared out Brad Shields off the ball.
With Sarries pushing, Stooke crossed against the run of play with minutes remaining to make the scoreline 26-13, although there was still time for Tompkins to go over in the corner to ensure a losing bonus point for his side.
Second-placed Saracens cut Leicester’s lead at the top of the Premiership table to seven points after the Tigers lost to Sale Sharks on Sunday.
Wasps’ win keeps them eighth in the table, 11 points behind fourth-placed Gloucester in the race for the play-offs.
Wasps head coach Lee Blackett told BBC CWR:
“This was a big game in our season with regards to the league. But I also think this is a big result for here and getting lots of supporters.
“The most important thing for the team is the league points and staying in touch. There were teams above us who got points. They could quite easily pull away before you know it.
“The only disappointing thing was how many points we got on the board. I felt like we controlled the field position. Off the back of set-pieces we didn’t get the rewards. We let them off.”
Saracens coach Kevin Sorrell:
“The game left us frustrating feeling overall.
“We didn’t get any field position in the first 20 minutes and that was caused by a combination of our errors and ill-discipline.
“We came on strong in the second quarter but the second half was an exact replica of the first.”