Paris - French Top 14 leaders Montpellier ran in six tries in a 43-20 thumping of Toulon on Sunday to continue their 100 percent start to the season, as Dan Carter's Racing 92 held off a spirited Oyonnax 25-13.
Aaron Cruden, Nemani Nadolo and Joe Tomane were among the try-scorers as Montpellier laid down a serious marker for the rest of the season.
Vern Cotter's side lead Racing by five points at the top of the early table, with a side boasting the likes of France No 8 Louis Picamoles and former New Zealand flyhalf Cruden looking in imperious form.
This match against three-time European champions Toulon promised to be Montpellier's toughest test so far after victories over Agen, Oyonnax and Castres.
But the 2016 Challenge Cup winners overcame a difficult start to the second half to blow away their visitors.
Josua Tuisova grabbed an early try for Toulon, after Montpellier scrumhalf Ruan Pienaar had slotted over a penalty.
In-form Montpellier hit back though, as Cruden and Nemani Nadolo crossed before half-time, with Pienaar adding the extras on both occasions.
Francois Trinh-Duc kicked penalties either side of half-time to drag Toulon to within just four points, only for Paul Willemse to score Montpellier's third try before the hour mark, with Pienaar taking his points tally to nine with the conversion.
Former England wing Chris Ashton sprinted away to score his second try since joining Toulon from reigning European champions Saracens, with Trinh-Duc's kick cutting the deficit back to four.
The game turned with quarter of an hour to play when Georgian international Mamuka Gorgodze was sin-binned, with Montpellier quickly putting the game to bed with a penalty try.
Australian winger Tomane came on as a replacement and touched down try number five, before South Africa centre Francois Steyn strolled over to rub extra salt into Toulon's wounds.
Fijian forward Leone Nakarawa, Virimi Vakatawa and Marc Andreu scored first-half tries for Racing in Paris, with Quentin Etienne denying Racing a bonus point with a try for Oyonnax.
The win is the capital-city side's third from four games so far this season.
Legendary flyhalf Carter opened the scoring with a penalty early on before Nakarawa burrowed over, with Carter adding the extras.
Ben Botica replied with a penalty for the away side, before France international Vakatawa grabbed his second try in as many matches, which was also converted by Carter.
Vakatawa's fellow wing Andreu looked to have ended the match as a contest and put Racing well on their way to the bonus-point victory they needed to take top spot from Montpellier, when he made it 22-3 at half-time.
Carter was withdrawn at the interval with the game all but won, but aother Botica penalty and Etienne's converted try cut the gap to just nine points.
In the New Zealander's absence it was left to scrumhalf Maxime Machenaud to kick a crucial penalty with 20 minutes remaining, but despite a late charge that saw Machenaud have a try chalked off for a forward pass, Racing failed to force a bonus point.
On Saturday, Clermont recovered from last week's 51-20 humbling at La Rochelle by thrashing pointless Brive 62-6, while Toulouse thrashed Stade Francais 53-17.