Injury-hit Bristol extended their lead at the top of the Gallagher Premiership to 11 points with their first victory over Wasps since September 2006, winning 37-20.
Bristol had lost 13 consecutive games to Wasps, but 17 points from the boot of fourth-choice outside-half Tiff Eden and four tries were enough for Bears to break that losing run.
Eden kicked three penalties and four conversions, with Bristol’s tries coming from Piers O’Conor, Joe Joyce, Chris Vui and Niyi Adeolokun.
Sione Vailanu and Josh Bassett scored Wasps’ tries, with Jimmy Gopperth adding two penalties and two conversions as they crashed to a sixth defeat in their last seven Premiership fixtures.
A careless knock-on from Jacob Umaga gifted Bristol an early period of pressure, but determined defence from the visitors kept their line intact before Wasps broke out to take the lead through a Gopperth penalty.
His successful kick took him past 1,000 points for the club in competitive matches, but the hosts should have drawn level only for Eden’s 40-metre penalty to rebound back off a post.
Gopperth then had the chance to extend Wasps’ lead with a kick at goal, but his side opted for an attacking line-out and it paid immediate dividends when their number eight Vailanu, on his first appearance for six months, burst away from a maul to score.
Gopperth converted from in front of the posts to give Wasps a 10-point lead, but the home side responded with an excellent try when Charles Piutau, taking the ball at first receiver, ghosted though the defence to send O’Conor over.
Eden converted and added a straightforward penalty before the visitors suffered an injury blow when their experienced lock James Gaskell was forced to leave the field.
Eden put Bears in front for the first time with a penalty before he and Gopperth exchanged further penalties to leave Bristol with a 16-13 interval lead.
Three minutes after the restart, Gopperth missed from long range before Bristol withdrew former Wasp Nathan Hughes, with Vui coming on to replace him.
Bears continued to have the better of possession and territory but apart from Piutau’s spark they lacked the cohesion and flair to make it count as the conditions worsened.
A penalty from Eden hit a post for the second time in the match, but the ball fell favourably for his side allowing Joyce to force his way over for his first Premiership try.
Remarkably, another penalty from Eden struck a post before Bristol made the game safe when Adeolokun finished off some skilful handling for their third try.
With two minutes remaining, spirited Wasps picked up a consolation try when Ben Vellacott darted away to send Bassett over, but Bristol had the final say as Vui forced his way over for the bonus point.
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