Paris - Clermont Ferrand thumped Stade Francais 46-10 and scored six tries on the way as the Top 14 leaders enjoyed a rousing performance on Friday.
They now have 46 points from their 14 games ahead of La Rochelle on 41.
The big game of the week sees Montpellier host mega-rich Toulon in Friday's late game in an encounter rendered all the more important by each side's European struggles.
Clermont's tries were scored by Adrien Plante on 22 and 32, Patricio Fernandez on 43, Noa Nakaitaci on 58, Damien Chouly on 73 and Sitaleki Timani two minute from time.
"I'm happy to have done my bit," Plante said after the game. "I'm getting back to my best form."
Clermont coach Franck Azma said his players had been very focussed.
"I was also happy to see them enjoying themselves so much too," he said