Grenoble claimed a 36-14 win over Bayonne in Friday's Amlin Challenge Cup Pool Four all-French affair but they will not progress to the knockout stages.
With Wasps having won the Pool and Bayonne already having secured second place, Grenoble were playing only for pride and to avenge their earlier defeat by their Top 14 rivals.
Hendrik Roodt scored the home side's first try of the night following a James Hart penalty before Bayonne hit back with a kick from Stephen Brett and Jean Monribot's converted try.
Brett scored another penalty just before the break to give the visitors a 13-8 lead at the break, but Grenoble were not done and came out firing in the second half, with two quickfire tries from Fabien Alexandre and Ratu Ratini, with Hart adding a conversion.
Bayonne fly-half Brett cut the gap with another penalty kick but Matthieu Nicolas' try for the home side extended Grenoble's advantage, with Vincent Campo scoring the fifth, Hart again adding a conversion and Julien Carminati scoring the other to wrap up victory.