Scottish scrumhalf Greg Laidlaw claimed 18 points as French Top 14 leaders Clermont ended La Rochelle's run of seven straight wins with a five-try, 44-19 victory on Sunday.
Laidlaw scored one of his team's tries and booted two conversions and three penalties -- all in the first half -- as Clermont stretched its unbeaten run in all competitions to three months.
"We knew that La Rochelle would arrive with very good intentions and it was important to test ourselves," said Clermont coach Franck Azema.
"Our forwards had a great start. We gave away just three penalties -- in terms of discipline, that's a very high level. It's good way to start 2019."
Clermont was rarely threatened on Sunday, racing to a 13-0 lead in just 23 minutes thanks to two penalties from Laidlaw, who also converted his own try.
Former All Blacks back-rower and La Rochelle skipper Victor Vito and replacement winger Geoffrey Doumayrou kept their team in touch either side of a Peceli Yato try on the stroke of half-time.
Clermont made the most of La Rochelle's indiscipline, being awarded a penalty try in the 57th minute for a 30-12 advantage.
In all, the visitors gave up 19 penalties and had three players sent to the sin bin.
George Moala and Tim Nanai-Williams added second-half tries for Clermont as the leaders grabbed a bonus point.
© Agence France-Presse