Clermont closed the gap on Top 14 leaders Toulon on Sunday with a 48-3 win over Bayonne, while Biarritz did just enough to beat bottom team Mont-de-Marsan.
In other early matches on Sunday, Grenoble defeated Bordeaux 19-9 and Toulose beat Castres 18-16. The evening fixture saw Montpellier secure a deserved 54-16 victory against Stade Francais.
Clermont Auvergne 48-3 Bayonne
Clermont issued a warning to their Top 14 rivals with a clinical display against their hapless opponents - running in six tries, with Wesley Fofana and Napolioni Nalaga bagging a brace.
There were further touchdowns by Jean-Marcellin Buttin and Benson Stanley while France international scrum-half Morgan Parra was flawless with the boot, kicking all the penalties and conversions that came his way.
Benjamin Boyet managed Bayonne's only points with a penalty on a tough afternoon for the visitors.
Racing Metro 40-6 Agen
Racing never looked in much trouble against Agen once they'd established a 20-6 lead at half-time.
Flanker Camille Gérondeau led the way for the Parisian outfit, crossing twice, and Argentine wing Juan Imhoff also touched down.
The rest of their points came via accurate goal-kicking from Maxime Machenaud, who added 25 points. Agen's only points came through two penalties from Conrad Barnard.
Mont de Marsan 18-19 Biarritz
Biarritz were made to fight before they secured victory against their hosts.
They opened the scoring inside the opening five minutes when they were awarded a penalty try after Imanol Harinordoquy was held back without the ball close to the try-line.
Biarritz's other points came through a conversion and four penalties from veteran scrum-half Dimitri Yachvili. Thibault Duvallet scored all Mont de Marsan's points via six penalties.
Grenoble 19-9 Bordeaux-Begles
Grenoble strengthened their position in the table with a deserved home win over Bordeaux.
The home side's full-back Fabien Gengenbacher scored the only try of the match and their other points came through a conversion and four penalties by Valentin Courrent.
Castres 16-18 Toulouse
Lionel Beauxis's boot guided Toulouse to a narrow victory but the visitors were made to sweat, especially during the closing stages.
Castres wing Marc Andreu scored the game's only try, early in the first half, and Rory Kockott kept his side in the match with a conversion and three penalties.
Montpellier 54-16 Stade Francais
Montpellier claimed a convincing win which keeps their play-off hopes alive.
The home side ran in six tries with Francois Trinh-Duc, Timoci Nagusa, Julien Tomas, Maximiliano Bustos, Thomas Combezou and Kelian Galletier all getting their name onto the scoresheet.
For Stade, Olivier Missoup scored a try and Jerome Porical slotted a conversion and three penalties.