Preview: Top 14, Round 23
Clermont, bidding for just their second Top 14 crown after 2010, lead the way with 75 points from 22 games, with four matches left in the regular season.
But the leaders have been showing signs of nerves with their eight-game winning run snapped by Racing 92 last weekend while Toulon's woes continued with a 12-10 defeat to Toulouse.
Bernard Laporte's Toulon have already lost their European title and have now lost ground in the race for the top two places, which allows direct qualification for the semifinals.
Toulouse moved fifth and closer to the play-offs with the top six teams at the end of the regular season entering the knock-out phase.
In-form Montpellier, confident after their 51-10 whipping of Grenoble last weekend, are now just two points off Clermont in second with Toulon a further five adrift, equal on 68 points with Racing 92.
Clermont travel to lowly Pau on Saturday with Toulon facing a stiffer test at home against Castres, while Montpellier travel to La Rochelle.
Castres, sitting sixth, and Bordeaux-Begles, seventh, are separated by just a point and are both in the fray for a play-off spot.
Castres have been gaining momentum – accumulating 19 points in their last five matches – including four wins, two with bonus points for just one loss.
They have also been explosve in attack with 17 tries in their last five away games.
Wing Remy Grosso and hooker Brice Mach are near to returning from injury and as their replacements have proved up to the job coach Christophe Urios is spoilt for choice.
"The staff have done their job, now it's down to the players. It's over to them to give it everything they have," said Urios.
Bordeaux's 32-25 win over Stade Français last weekend, meanwhile, allowed them to break a negative spiral and stay in touch with Castres.
Bordeaux face a tougher task on paper than Castres with three away games including one at Montpellier a week after the southern side compete in the European Challenge Cup Final and another at Toulon to conclude the regular season.
Friday's game at Grenoble will be an important one for Bordeaux.
"We have nothing to lose, just the chance to qualify," said Bordeaux captain Louis-Benoît Madaule added.
Former 19-times champions Toulouse host tailenders Agen as champions Stade Francais are facing a key test in their troubled season at home to Oyonnax and still not free of relegation worries.
The Paris side, impressive winners of Europe's top club competition last year, are currently third from bottom following their 25-35 loss away to Bordeaux.
The only clubs below them are Agen on 21 points and Oyonnax on 22, 10 points behind Stade.
The bottom two teams are relegated which leaves the club concerned what might happen if the Parisians fail to see off Oyonnax at their Stade Jean Bouin stadium.
Top 14 – Round 23 fixtures:
Grenoble v Bordeaux-Begles
La Rochelle v Montpellier
Pau v Clermont
Stade Francais v Oyonnax
Brive v Racing 92
Toulouse v Agen
Toulon v Castres
Agence France-Presse
