In amongst it: Montauban visit Stade Français in Round 18
Toulouse host Clermont on Saturday in potentially the most attractive game of the Top 14 season while Brive, Albi and Dax are engaged in a three-way battle to avoid relegation.
The result of the top of the table clash in Toulouse will be strictly academic to the other 12 clubs since the two leaders are so far ahead.
At the other end of the table however this could be a make or break weekend with Brive hosting Dax in a game that could seal the visitor's fate.
Biarritz have a golden opportunity to regain fourth spot from Perpignan when the Basques host Pro D2 bound Auch. Perpignan have a more difficult task as Bayonne visit the Catalan coast.
In the other competition within a competition Castres, Montpellier and Montauban will be desperate for points as they vie for a spot in the Heineken Cup.
Fixtures:
Friday April 18
Bourgoin v Castres
Saturday April 19
Toulouse v Clermont
Biarritz v Auch
Albi v Montpellier
Brive v Dax
Perpignan v Bayonne
Stade Français v Montauban
Table after Round 17
1. Clermont 67
2. Toulouse 66
3. Stade Français 53
4. Perpignan 48
5. Biarritz 47
6. Castres 42
7. Montauban 40
8. Montpellier 38
9. Bourgoin 35
10. Bayonne 33
11. Brive 32
12. Albi 26
13. Dax 22
14. Auch 14
Previews:
CS Bourgoin-Jallieu v Castres Olympique
Both teams lost last week to Clermont and Perpignan respectively.
Bourgoin have a very good home record this season but their away form has seen them fall behind the pack racing for a place in the Heineken Cup.
A win against Castres is thus vital if they want another taste of Europe's top competition.
Castres will fancy their chances of winning at Pierre-Rajon though. 32-17 winners the last time the teams met, Castres have been the surprise of the season.
It will be a special day for France and Castres captain Lionel Nallet. An ex-Bourgoin player, Nallet is rumoured to be set to move back to his home town and club at the end of the season.
Bourgoin will be without live-wire scrum-half Morgan Parra who limped off the field in Clermont last weekend.
Venue: Pierre-Rajon
Kick-off: 20:30
Referee: Christophe Berdos
Touch judges: Patrick Bellet, Jean-Luc Gonzalez
Assessor: Daniel Pascal, Marc Desclaux
Television match official: Jean-Claude Levrier
Stade Toulousain v Clermont Auvergne
It's the match we've all been waiting for. Second hosts first in front of a full-house in what many expect to be the best game of the season.
The two clubs have been head and shoulders above everyone else and top the statistics in every domain.
'Throwing' the game like they did against Stade Français a few weeks ago is out of the question for Toulouse.
One week ahead of their Heineken Cup semi-final against London Irish, Toulouse will line up their first team in the hope of gaining some rhythm and ending Clermont's eight game winning streak.
There will be no lack of big names on the park, the only expected absentees will be French winger Julien Malzieu who has a ankle niggle, and Jean-Baptiste Poux who has a pulled calf muscle.
Venue: Ernest Wallon
Kick-off: 15:00
Referee: Franck Maciello
Touch judges: Hervé Gilard, Eric Briquet Campin
Assessor: Hubert Dubes, Daniel Irazoqui, Bernard Perez
Television match official: Gérard Borreani
Biarritz Olympique v FC Auch Gers
After weeks of criticism, injuries, poor form and facing a sometimes unforgiving home crowd, Biarritz's resounding win in the Basque derby last weekend was a welcome tonic.
For the first time this season they scored an attacking bonus point as their back-line finally gelled in the second-half.
The BO injury list has at long last been cut down to a manageable size, and this match against bottom of the table Auch is the perfect opportunity to turn last week's spark into a flame and re-ignite their campaign for a semi-final berth.
Auch are in a hopeless situation. They played a good first-half against Montauban last week but they've just been out of their depth in the Top 14 this season.
They will also be without arguably their best player, prop Fabien Barcella.
With matches against the top four still on the menu, their trip to Biarritz is the first step on a long road to the end of the season.
Venue: Parc Aguilera
Kick-off: 17:30
Referee: Bernard Dal Maso
Touch judges: Denis Grenouillet, Didier Barnagaud
Assessor: Jean-Louis Lamy, Roger Duhau
Television match official: Daniel Gillet
SCA Albi v Montpellier HRC
Montpellier's season has been a roller coaster ride of spectacular highs and earth shattering lows. After two wins on the trot against Brive and Castres, the current trend seems to be an upward curve.
Just two points behind Montauban, who occupy seventh spot (which could mean Heineken Cup qualification if Toulouse win the competition), Montpellier have everything to play for.
French international Louis Picamoles says the young side are not getting ahead of themselves though.
"Last year, we came within one game of being relegated and I don't think that having a new stadium means the team are now semi-final or European Cup pretenders," Picamoles told rugbyrama.
"We know we have skills, we know that we have the potential to get there, but it's not an objective for us. It's not a taboo but we don't talk about it."
Albi are on a slippery slope at the moment. Just four points clear of the relegation zone they're living on the edge and a point or two will be very welcome.
Venue: Stade Municipal
Kick-off: 17:30
Referee: Akim Hadj Bachir
Touch judges: Gérard Gacon, Jean-Christophe Clot
Assessor: Francis Coup, Michel Messan
Television match official: Jean-Marie Combe
CA Brive-Corrèze v US Dax
This is potentially the most significant match of the weekend. Like fellow strugglers Dax and Albi, Brive lost last weekend (to Montpellier) but Olivier Magne's team did score a vital bonus point.
Six points clear of Albi and ten clear of their opposition on Saturday, if Brive can pull off a win, it might just be enough to secure a spot in the top flight next year.
For Dax however, it's now or never. Already second to last, losing to Brive would see their hopes of staying up slip away.
Dax have some serious regrets to get over. Last weekend they came within ten minutes of upsetting Stade Français, but just like they did in the away fixture in December, the Dacquois lost narrowly.
But that loss would have given them some hope. They managed to walk away with a defensive bonus point against a quality side and if Thomas Lièvremont can rally his team-mates, survival is still a possibility.
Just four points behind Albi, who are likely to lose to Montpellier, a victory for Dax would mean they will they will host Abli a week later with every hope of climbing out of the relegation zone for good.
Venue: Amedée-Domenech
Kick-off: 17:30
Referee: David Rosich
Touch judges: Claude Tajan, Fernand Pereira
Assessor: Claude Rouve, Jean Lavergne
Television match official: Jean-Christophe Gastou
USA Perpignan v Aviron Bayonnais
Unbeaten in seven matches Perpignan will be looking for a bonus point win to keep Biarritz at bay and maintain fourth spot.
Bayonne did the Biarritz cause a world of good by capitulating 20-0 to their Basque rivals last weekend and Perpignan will be hoping for a similar favour.
Perpignan took three days off at the start of the week and only started their preparation on Thursday. Coach Jacques Brunel said his team needed both a mental and physical break.
The teams last met under very different circumstances and Bayonne thumped a down-on-their-luck Catalan side 35-8.
How times have changed. Bayonne's form is about as bad as Perpignan's is good.
They've gone down in five of their last six matches, including an unexpected loss to Dax, and are now dangerously close to being embroiled in the relegation battle.
Venue: Aimé-Giral
Kick-off: 17:30
Referee: Eric Gauzins
Touch judges: Olivier Migne, Régis Gabard
Assessor: Jean-Marie Combe, Patrick Robin
Television match official: Daniel Dartigeas
Stade Français v Montauban
After a dip in form a few weeks ago the Stade Français train is back on track and looking to steam to their fourth consecutive win. Easier said than done though.
Stade struggled to beat lowly Dax last week and were on the wrong end of the 24-16 scoreline the last time they played Montauban.
But neither of those games where in Paris and Stade Jean Bouin has become a veritable fortress for the defending champions.
Montauban have the firepower to cause an upset through. Just two points behind Castres, and the last Heineken Cup qualifying spot, the visitors will be looking to build on their victory over Auch last weekend.
Venue: Jean Bouin
Kick-off: 20:30
Referee: Pascal Gauzere
Touch judges: Gilbert Darrieutort, Didier Dussaut
Assessor: Michel Kazmierczak, Daniel Pruvot
Television match official: Daniel Irazoqui