Toulon booked their place in the Top 14 play-offs with a narrow win at home to defending champions Toulouse on Saturday.
A losing bonus point was enough for Toulouse to retain the championship lead however as Clermont lost on the road to Castres.
Racing join Castres in the play-offs after eliminating Parisian rivals Stade FranÃ§ais from the race in a tight battle in the capital.
Brive are now favourites to be relegated with Lyon after losing heavily at home to Bordeaux-BÃ¨gles while Bayonne won with a bonus point against Agen.
Elsewhere, Perpignan ensured their survival with a bad-tempered win over Lyon.
On Friday, Biarritz also secured their place in the top division next season by getting a losing bonus point in Montpellier.
Montpellier 21-16 Biarritz
Toulon 25-22 Toulouse
Bayonne 31-10 Agen
Brive 9-23 Bordeaux-BÃ¨gles
Castres 30-19 Clermont
Perpignan 34-22 Lyon
Racing MÃ©tro 19-13 Stade FranÃ§ais
RC Toulon 25-22 Stade Toulousain
Stade Felix Mayol, Toulon
A huge result for Toulon who came from behind to beat a near-full-strength Toulouse side and virtually assure a home play-off in the process.
Toulouse have now lost six of their last nine games in all competitions despite having started the match in great style, taking a 16-8 lead into the half-time break thanks to a try from Vincent Clerc.
It seemed like Toulouse had got their mojo back as they were playing great rugby, but Toulon fought back in the second period with Steffon Armitage continuing his strong recent form with the winning try in the 65th minute.
Lionel Beauxis and Jonny Wilkinson traded early penalties in a pulsating match played in perfect conditions, the Toulouse man hitting a second before the home side hit back.
Toulon centre Matt Giteau made a scything break through a porous defence before sending out an inch-perfect pass to Alexis Palisson, the France winger crossing in the corner for a try Wilkinson failed to convert.
Clerc responded with a well-taken try after a similar miss-pass from Beauxis, who nailed the extras and a 33rd minute penalty for a 16-8 Toulouse lead.
Welsh prop Eifion Lewis-Roberts was bundled over for a timely converted try early in the second-half for the hosts before Beauxis and Wilkinson again traded penalties.
Armitage scored the decisive five-pointer, jinking through under the posts after a period of sustained pressure.
Wilkinson converted to make it 25-19 with 15 minutes to play, Beauxis hitting a penalty shortly after, but the home side held out for the victory.
Tries: Palisson, Roberts, Armitage
Cons: Wilkinson 2
Pens: Wilkinson 2
Pens: Beauxis 5
Toulon: 15 Benjamin Lapeyre, 14 Alexis Palisson, 13 Geoffroy Messina, 12 Matt Giteau, 11 David Smith, 10 Jonny Wilkinson, 9 Sebastien Tillous-Borde, 8 Juan Martin Fernandez Lobbe, 7 Steffon Armitage, 6 Joe van Niekerk, 5 Christophe Samson, 4 Bakkies Botha, 3 Carl Hayman, 2 Sebastien Bruno, 1 Eifion Roberts.
Replacements: 16 Mickael Ivaldi, 17 Laurent Emmanuelli, 18 Jocelino Suta, 19 Pierrick Gunther, 20 Gaby Lovobalavu, 21 Luke Rooney, 22 Fabien Cibray, 23 Davit Kubriashvili.
Toulouse: 15 Clement Poitrenaud, 14 Vincent Clerc, 13 Florian Fritz, 12 Yannick Jauzion, 11 Yves Donguy, 10 Lionel Beauxis, 9 Luke Burgess, 8 Louis Picamoles, 7 Thierry Dusautoir, 6 Jean Bouilhou, 5 Patricio Albacete, 4 Yoann Maestri, 3 Cencus Johnston, 2 Christopher Tolofua, 1 Jean-Baptiste Poux.
Replacements: 16 Victor Paquet, 17 Daan Human, 18 Gregory Lamboley, 19 Yannick Nyanga, 20 Jean-Marc Doussain, 21 Yann David, 22 Gillian Galan, 23 Yohan Montes.
Aviron Bayonnais 31-10 SU Agen
Stade Jean Dauger, Bayonne
Bayonne's expensively assembled squad finally produced the goods, outscoring their visitors four tries to one to move within touching distance of safety.
Bayonne waited for the second last round of the championship to record their first bonus point win and climb out of the relegation zone, five points clear of Brive.
Brive's failure to get a bonus point means that Agen are also safe.
Agen led 10-7 thanks to a try from full-back Brice Dulin, who cancelled out Bayonne centre Sam Gerber's touchdown.
But the Bayonne pack dominated the second half, winning a penalty try and setting up two more.
Tries: Gerber, Roumieu, Penalty try, Boutaty
Cons: Potgieter 4
Yellow cards: Telefoni (Agen - 16th min), Fa'aoso (Agen - 50th min); Boyoud (Bayonne - 62nd min)
Bayonne: 15 Cedric Heymans, 14 Yoann Huget, 13 Sam Gerber, 12 Lionel Mazars, 11 Marvin O'Connor, 10 Jacques-Louis Potgieter, 9 Mike Phillips, 8 Dwayne Haare, 7 Jean Jo Marmouyet, 6 Guillaume Bernad, 5 Mark Chisholm, 4 Abdellatif Boutaty, 3 Neemia Tialata, 2 David Roumieu, 1 Aretz Iguiniz.
Replacements: 16 Francois Da Ros, 17 Renaud Boyoud, 18 Troy Flavell, 19 Julien Puricelli, 20 Cedric Garcia, 21 Benjamin Boyet, 22 Joe Rokocoko, 23 Victor Manukula.
Agen : 15 Brice Dulin, 14 Saimoni Vaka, 13 Junior Pelesasa, 12 Jamie Robinson, 11 Romain Edmond Samuel, 10 Conrad Barnard, 9 Maxime Machenaud, 8 Marc Giraud, 7 Adri Badenhorst, 6 Jean Monribot, 5 Lisiate Fa'aoso, 4 Dewald Senekal, 3 Gert Muller, 2 Jalil Narjissi, 1 Semisi Telefoni.
Replacements: 16 Julien Janaudy, 17 Arsene Nnomo, 18 Pat O'Connor, 19 Pierre Julien, 20 Alexis Bales, 21 Manu Ahotaeiloa, 22 Silvere Tian, 23 Beka Sheklashvili.
CA Brive CorrÃ¨ze 9-23 Union Bordeaux-BÃ¨gles
Brive are almost certain to be relegated after failing to come up with the goods when it mattered most.
Now five points adrift of Bayonne, Brive now face the prospect of not only having to win with a bonus point in their final away game at heavyweights Clermont, but also need Bayonne to lose, without a defensive bonus point, away to Castres.
Pens: Swanepoel 3
Tries: Connor, le Bourhis
Cons: Lopez, Fraser
Pens: Lopez 3
Yellow cards: Mela (Brive - 62nd min); Bias (Brive - 75th min)
Brive: 15 Scott Spedding, 14 Jacques Boussuge, 13 Arnaud Mignardi, 12 Riaan Swanepoel, 11 Ronnie Cooke, 10 Shane Geraghty, 9 Jean-Baptiste Pejoine, 8 Antonie Claassen, 7 Alexandre Bias, 6 Thibault Dubarry, 5 Arnaud Mela, 4 Julien Ledevedec, 3 Vassil Kakovin, 2 Virgile Lacombe, 1 Pablo Henn.
Replacements: 16 Iuri Natriashvili, 17 Jefferson Poirot, 18 Retief Uys, 19 Poutasi Luafutu, 20 Simon Azoulai, 21 Mathieu Belie, 22 Jamie Noon, 23 Pablo Cardinali.