Grenoble claimed yet another big scalp in the Top 14 on Saturday as they maintained their unbeaten home record with victory over Castres.
Elsewhere, both Stade Francais and Perpignan relied on their goal-kickers to edge past Bayonne and Bordeaux-Begles respectively.
Grenoble 14-12 Castres
Grenoble climbed into the top six on the back of their third straight win which was set up by a fifth-minute try from winger Lucas Dupont.
Castres scored two tries of their own through Marc Andreu and Thierry Lacrampe but were always chasing the game after Grenoble fly-half Blair Stewart's neat drop-goal early in the second period gave the hosts a healthy nine-point lead.
Stade Francais 21-13 Bayonne
Stade Francais could not breach the Bayonne defence but put in a workman-like display to bounce back from a heavy defeat last week with full-back Jerome Porical kicking all their points.
Bayonne number eight Dwayne Haare scored early to give the visitors the lead, but Porical had kicked his side into a 15-10 half-time advantage and added six further points to see them home after the break.
Perpignan 26-16 Bordeaux-Begles
Perpignan came from a point down with nine minutes remaining to see off Bordeaux-Begles, ultimately denying the visitors a losing bonus-point.
UBB went 16-15 ahead thanks to a brilliant 90m try from full-back Metuisela Talebula, but the Catalans had the last laugh as David Mele kicked them back in front with a penalty before Gavin Hume's last-minute try wrapped up the win.
Mont-de-Marsan 12-16 Toulouse
Toulouse were a long way from their best but emerged triumphant as they did just enough to overcome minnows Mont-de-Marsan.
Toulouse forwards coach/hooker William Servat was at the back of a maul that rumbled over the line as the visitors lead 10-6 at the break and a couple of Luke McAlister penalties would prove sufficient as the hosts could muster only four kicks of their own.
Clermont Auvergne 36 -18 Montpellier
Clermont held onto second place with a hard-fought 36-18 win over Montpellier at Parc Des Sports Marcel Michelin as Wesley Fofana and Jean-Marcellin Buttin added to a penalty try.
Clermont led 20-13 at the break thanks largely to centre Fofana, who scored one try and created another for Buttin, in reply to Montpellier prop Maximiliano Bustos's score-opening try in the third minute and the boot of Morgan Parra saw the hosts home in the second period.
Which side will top the Top 14 regular-season?