Bristol recorded a 37-19 victory at Toulon in Pool Two of the European Challenge Cup on Friday night.
The Guinness Premiership's basement club put their woeful domestic form behind them to record their first victory for almost two months.
Lee Robinson scored in either half including his team's fourth as Bristol racked up a bonus point win at Stade Felix-Mayol.
Nathan Budgett crashed over for the first on 23 minutes after Ed Barnes and Sebastien Fauque exchanged penalties before Robinson skipped through fir his first to hand Bristol a shock 20-3 half-time lead.
Toulon, who had rested several first choice players, hit back through centre Olivier Grimaud and 11 points from the boot of Fauque to trim the lead to 23-19.
But Bristol bellied their league status in the final eight minutes as England scrum-half Shaun Perry and Robinson settled the tie.
The victory lifts Bristol to second in the pool, four points behind leaders Northampton, though their hopes of progressing as one of the tournament's best runners-up remain slim after just two victories from five.
Dax recorded their first victory of the campaign after beating Rovigo 22-20 at Stade Marice Boyau.
Rovigo outscored their hosts two tries to one following scores from prop Bruno Fortuna and wing Filippo Arestusini.
But Dax fly-half Maxime Petitjean kicked 17 points including the conversion of a penalty try as the French outfit struggled to break the stubborn Italian defence.
Bayonne inflicted a fifth straight defeat for French rivals Mont de Marsan in Pool Five with a 33-19 victory at Stade Jean Dauger. Four penalties by scrum-half Cedric Garcia gave Bayonne a 12-9 lead at half-time before tries from wing Filimone Bolavucu, centre Vincent Invigo and replacement Louis Massabeau completed the victory.
