Fritz Lee's Clermont put paid to Castres 42-13, despite the presence of former All Blacks Rudi Wulf and Sitiveni Sivivatu in the Castres backline.
Former Taranaki wing and current Manu Samoa rep Paul Perez scored an important try as Toulouse won 33-25 at Montpellier. Neemia Tialata was at tighthead prop and Luke McAlister first five for the away team.
In the Guinness PRO12, new Leinster skipper Isa Nacewa scored a try and kicked a conversion in the 27-3 win at Treviso. New signing, North Harbour lock Hayden Triggs, turned out for Leinster.
Pat Lam's Connacht edged Edinburgh 14-9 to stay in touch with Wayne Pivac's Scarlets, while Francis Saili's Munster beat the Ulster of Sean Reidy and Nick Williams.
In the Aviva Premiership, Nick Evans' boot was to the fore, his 28 points, including eight penalty goals, decisive in Harlequins' 38-28 win at Bath.
Former Highlanders and Canterbury wing Telusa Veainu scored a late try to help Leicester Tigers to a 24-16 victory over Wasps. Bay of Plenty halfback Jono Kitto came off the bench for Leicester. Wasps No 10 Jimmy Gopperth was binned for a high tackle on Tigers' captain Mathew Tait.
Daniel Braid, with TJ Ioane, Bryn Evans and Johnny Leota by his side, led Sale Sharks to a 20-13 win over Northampton. Thomas Waldrom's Exeter Chiefs stomped all over the Newcastle Falcons 41-3, while former Tasman Makos lock Tevita Cavubati, playing for Worcester, lost to Gloucester 24-22.
Saracens defeated London Irish 24-14, for whom Asaeli Tikoirotuma scored a try and incurred a yellow card. Sean Maitland was on the other wing for the Exiles. Former Canterbury and Chiefs lock Matt Symons also played for London Irish.