Castres maintained their remarkable run towards Top 14 domination with a convincing 44-10 win over bottom club Albi at Stade Pierre Antoine on Sunday.
While other luminaries in the top half of the table - most notably Perpignan - fell to surprise defeats, the Tarnats were comfortably ahead at half-time and needed only a second-half try from Chris Masoe to seal the deal with a bonus point on their 44-10 win.
Clermont kept up the pace behind Castres with an equally stunning 39-3 win over Toulon while Toulouse narrowly beat Bayonne 15-13.
Perpignan fell 29-9 to a hitherto struggling Brive side in the day's big upset, while Stade Français continued to labour against Montauban in a desperate 6-6 draw.
Biarritz suffered little difficulty with a comfortable 26-10 home win over Montpellier, while Racing Metro's run up the table suffered a stutter as they lost 18-17 at home to lowly Bourgoin.
Results, Sunday, January 3
Castres 44-10 Albi
Racing Metro 17-18 Bourgoin
Montauban 6-6 Stade Français
Brive 29-9 Perpignan
Biarritz 26-10 Montpellier
Clermont 39-3 Toulon
Bayonne 13-15 Toulouse
1 Castres 56
2 Clermont 52
3 Toulouse 49
4 Racing Metro 48
5 Perpignan 45
6 Biarritz 42
7 Toulon 42
8 Stade Français 41
9 Brive 38
10 Montpellier 33
11 Montauban 32
12 Bourgoin 31
13 Bayonne 25
14 Albi 19
Castres Olympique 44-10 SCA Albi
Stade Pierre Antoine, Castres
Castres march on. There ae stiffer tests to come than a home clash with the bottom side, but the season's surprise package wasted little time in building up an unassailable lead.
The home side led 22-3 after just 26 minutes, with tries from Marc Andreu, Cammy McIntyre and a penalty try, bolstered by two conversions and a penalty from Romain Teulet, punctuating a storming opening half hour.
Albi hit back with a try by Kevin Boulogne, who converted it himself and had notched an early penalty, but Chris Masoe's 50th-minute score put Castres back three tries ahead for the bonus point victory and they closed out the game comfortably with two more tries from McIntyre and Joe Tekori.
Racing Metro 92 17-18 CS Bourgoin-Jallieu
Stade Yves Du Manoir - Colombes (Paris)
Racing's run of nine victories came to an ignominious end with defeat to Bourgoin, who were good value for their win despite nearly throwing it away.
Bourgoin charged into an 11-0 lead early on with a penaty and drop goal from Benjamin Boyet and a try from prop Camille Levast.
Rising star fly-half Jonathan Wisniewski converted Johnny Leo'o's try to make the score 11-7 at the break, but Albert Vulivuli's second-half score and Boyet's conversion restored Bourgoin's 11-point lead.
Wisniewski added a try, a drop goal and a conversion to make the game a one-pointer, but a missed penalty from Frans Steyn and a botched drop goal attempt from Wisniewski meant Bourgoin stumbled over the finish line.
Montauban 6-6 Stade Français
Stade Sapiac, Montauban
The less said about this game the better. Montauban led twice, first through a penalty from Cedric Rosalen, then from a drop goal by the same.
Lionel Beauxis replied both times with a penalty. That was it.
CA Brive-Corrèze 29-9 USA Perpignan
Stade Amédée Domenech, Brive
So it's true, Brive really can score tries! They scored three of them here on Sunday, three more than their illustrious visitors, meaning they claimed a bonus point.
At the hour, it was only 14-9, with Davit Khinchagishvili's early try the difference between the teams and Alexis Palisson and Steve Meyer exchanging three penalties each.
Palisson stretched the lead with another penalty, and then two quickfire tries from Palisson and Ronnie Cooke - both of them crackers - sealed the deal for the delighted home faithful.
Perpignan must now regroup as the momentum is fast running out of their season.
Biarritz Olympique 26-10 Montpellier HRC
Parc des Sports d'Aguilera, Biarritz
Business as usual for Biarritz, who are in excellent form at the moment after their poor start.
They ran in four scores in all, with Iain Balshaw marking his return from injury with one, young centre Arnaud Mignardi scoring two and Takudzwa Ngwenya - rapidly achieving mythical status in the Top 14 - running in another.
Dimitri Yachvili converted two and Olivier Sarramea another, while Montpellier's lone consolation was a score from number eight Marc Giraud.
Clermont Auvergne 39-3 RC Toulon
Parc des Sports Marcel Michelin, Clermont Ferrand
Clermont annihilated Toulon at the Stade Marcel Michelin, running in five tries in all in a devastating 39-3 win.
More disturbing for the Toulonnais - indeed, for any of the top clubs vying for the championship this year - was that the visitors were not exactly short of star quality. Jonny Wilkinson started with Felipe Contepomi outside him and Joe van Niekerk, Juan Martin Fernandez Lobbe and Saimone Taumoepeau all started in the pack.
Jamie Cudmore's first-half try and Morgan Parra's conversion was all that separated the teams by 50 minutes, with Clermont leading 10-3, but then the floodgates opened.
Parra, Julien Malzieu and Kevin Senio all weighed in with scores, added to by a penalty try and with Parra converting three of them and adding another penalty as Toulon sank without trace.
It's a statement of intent from Clermont though, who are well on course to peak at the right time of the season. Their eleventh final beckons - a lucky one this time?
Aviron Bayonnais 13-15 Stade Toulousain
Stade Jean Dauger, Bayonne
Toulouse secured a workmanlike win over Bayonne, courtesy of the accurate boot of Jean-Baptiste Elissalde, who nailed four penalties and a drop goal.
Bayonne were perhaps a shade unfortunate not to grab the win, particularly after a late try by Benjamin Fall and conversion by Cedric Garcia.
Garcia had the chance to win the match with the last kick of the game from 50m but sent the ball just to the right, leaving the Avirons in deep trouble six points adrift in the relegation zone.