Australian fly-half Jake McIntyre scored half his side's points as Clermont claimed a home win over Montpellier for the first time in five years with a 20-13 victory in the French Top 14 on Saturday.
McIntyre, a former Australia Under-20 international, slotted two conversions and a pair of penalties as hooker Mike Tadjer and former All Blacks playmaker Isaia Toeava crossed for last season's runners-up.
The last time Montpellier failed to win at Stade Marcel-Michelin was in February 2014 and the victory moves Clermont up to third place in the table.
"Matches against Montpellier are alway difficult, we've seen that over the last five seasons," Clermont coach Franck Azema said.
"It's certainly our roughest match since the start of the season but we controlled it well."
The visitors' scrum-half Benoit Paillague and McIntyre traded two penalties each within the opening quarter.
Tadjer crossed for the opening try of the game 12 minutes from the break.
As the half-time whistle blew a scuffle broke out as Montpellier's Kelian Galletier reacted badly to Tadjer's patronising tap on the head but referee Maxime Chalon only gave warnings to both sides.
The teams were equal 10 minutes into the second half as Youri Delhommel crossed and Paillague added the extras to bring the score to 13-13.
With 20 minutes remaining, 36-time All Black Toeava re-established Clermont's lead after a classy sidestep to beat Montpellier's defence five metres from their tryline.
McIntyre converted before missing a second straight penalty goal but Clermont held on for a long-awaited success.
Later on Saturday pressure builds on former South Africa coach Heyneke Meyer with his Stade Francais side sitting bottom of the table before a trip to 2018 champions Castres.
Leaders Lyon host second-placed Bordeaux-Begles with both clubs looking to maintain their unbeaten starts.
On Sunday, 13th-placed Racing 92 head to Pau before three-time former European champions Toulon, who have ex-All Blacks winger Julian Savea on the bench after he recovered from the flu, welcome La Rochelle.