Clermont Auvergne hammered fellow title hopefuls La Rochelle, who had won 10 of their previous 11 matches.
Greig Laidlaw claimed an 18-point haul as Clermont Auvergne returned to the summit of the Top 14 table with a 44-19 rout of high-flying La Rochelle.
Franck Azema's side made a huge statement at Stade Marcel-Michelin on Sunday, scoring five tries to extend their unbeaten run to 11 matches in all competitions.
Third-placed La Rochelle had won 10 of their previous 11 matches, but they were no match for rampant Clermont.
Laidlaw put the home side well on course for another victory when he threw a dummy and dotted down for a try which he converted before adding a second penalty.
Victor Vito's try got La Rochelle on the board, but Clermont led 23-7 at half-time courtesy of a Peceli Yato try, which Laidlaw converted after he was on target with a third penalty.
Geoffrey Doumayrou and Jone Qovu went over for La Rochelle either side of a penalty try for Clermont, which also resulted in Arthur Joly being sin-binned following the collapse of a scrum.
Indiscipline cost La Rochelle again when Alexi Bales became their third player to be yellow-carded, with George Moala and Tim Nanai-Williams adding further tries in a crushing victory which puts Clermont three points clear of Toulouse.