Clermont were deposed from the summit of the Top 14 standings on Saturday after losing to relegation-threatened Bayonne.
Toulon fell to seventh in the standings after being completely muscled in Brive.
Perpignan grabbed a losing bonus point in teh final minute away to Grenoble, who continue to climb up the table.
Montpellier held on for a narrow win at home to Bordeaux-BÃ¨gles while Biarritz's relegation battle with Oyonnax was called off due to the heavy rains on the Basque coast.
Stade FranÃ§ais are now the new leaders following their win over Castres on Friday.
Toulouse were the other big losers of the weekend as they dropped to sixth after failing to pick up a point away to Racing MÃ©tro.
Stade FranÃ§ais 32-6 Castres
Racing MÃ©tro 25-5 Toulouse
Bayonne 18-9 Clermont
Grenoble 25-19 Perpignan
Montpellier 28-23 Bordeaux-BÃ¨gles
Biarritz v Oyonnax - Postponed due to waterlogged pitch
Brive 23-10 Toulon
Aviron Bayonnais 18-9 ASM Clermont Auvergne
Stade Jean Dauger, Bayonne
This is a massive result for Bayonne, who climb out of the relegation zone.
For Clermont, failing to even grab a losing bonus point means they are now two points behind new league leaders Stade FranÃ§ais, whom they face next.
In driving wind and rain, on a soaked pitch, the Basque pack stepped up, especially at scrum time to allowed sharp-shooting Argentine wing Martin Bustos Moyano to kick the hosts to victory.
Pens: Bustos Moyano 6
Pens: Parra 3
Yellow card: Pierre
Bayonne: 15 Scott Spedding, 14 Martin Bustos Moyano, 13 Joe Rokocoko, 12 Gabiriele Lovobalavu, 11 Marvin O'Connor, 10 Santiago Fernandez, 9 Guillaume Rouet, 8 Dwayne Haare, 7 Jean Monribot, 6 Mark Chisholm, 5 Lisiate Faaoso, 4 Dewald Senekal, 3 Nemiah Tialata, 2 David Roumieu, 1 Aretz Iguiniz,
Replacements: 16 Anthony Etrillard, 17 JC Janse van rensburg, 18 Julien Puricelli, 19 Jean joseph Marmouyet, 20 Opeti Fonua, 21 Mathieu Belie, 22 Stephen Brett, 23 Gert Muller
Clermont: 15 Lee Byrne, 14 Noa Nakaitaci, 13 Aurelien Rougerie, 12 Benson Stanley, 11 Sitiveni Sivivatu, 10 Michael Delany, 9 Morgan Parra, 8 Elvis Vermeulen, 7 Julien Kazubek, 6 Alexandre Lapandry, 5 Loic Jacquet, 4 Julien Pierre, 3 Clement Ric, 2 Benoit Cabello, 1 Raphael Chaume,
Replacements: 16 Clement Jullien, 17 Etienne Falgoux, 18 Paul Jedrasiak, 19 Peceli Yato, 20 Ludovic Radosavljevic, 21 Uwanakoro Tawalo, 22 Jean Marcellin Buttin, 23 Vincent Debaty.
Referee: Salem Attalah
FC Grenoble 25-19 USA Perpignan
Stade LesdiguiÃ¨res, Grenoble
Grenoble climb into the top five but will regret missing out a bonus point after conceding a try with the final play of the game.
FCG led 10-3 at the end of an error-riddled first half thanks to a try from hooker Vincent Campo after driving maul.
The home pack continued to dominate as flank Fabien Alexandre score twice from close range.
But USAP would not go home empty handed as a sweeping move at the death saw Alasdair Strokosch put Karl Chateau over for a bonus-point saving try.
Tries: Campo, Alexandre 2
Cons: Hart, Courrent
Pens: Hart 2
Yellow card: Roodt
Pens: Hook 4
Yellow cards: Guirado, Taofifenua
Grenoble: 15 Fabien Gengenbacher, 14 Ratu Alipate,, 13 Geoffroy Messina, 12 Nigel Hunt, 11 Matthieu Nicolas, 10 Blair Stewart, 9 James Hart, 8 Florian Faure, 7 Fabien Alexandre, 6 Jonathan Best, 5 Benjamin Hand, 4 Hendrik Roodt, 3 Dayna Edwards, 2 Vincent Campo Castillo, 1 Kenan Mutapcic,
Replacements: 16 Laurent Bouchet, 17 Albertus Buckle, 18 Naude Beukes, 19 Henry Vanderglas, 20 Andrew Farley, 21 Julien Caminati, 22 Valentin Courrent, 23 Richard Choirat
Perpignan: 15 Joffrey Michel, 14 Watisoni Votu, 13 David Marty, 12 Sione Piukala, 11 Tommaso Benvenuti, 10 James Hook, 9 Tom Ecochard, 8 Justin Purll, 7 Alasdair Strokosch, 6 Jean Pierre Perez, 5 Romain Taofifenua, 4 Daniel Leo, 3 Giorge Jgenti, 2 Guilhem Guirado, 1 Sona Taumalolo,
Replacements: 16 Romain Terrain, 17 Sebastien Taofifenua, 18 Sebastien Vahaamahina, 19 Karl Chateau, 20 Tommaso Allan, 21 Lifeimi Mafi, 22 Richard Haughton, 23 Kisi Pulu.
Referee: Alexandre Ruiz
Montpellier HÃ©rault Rugby 28-23 Union Bordeaux-BÃ¨gles
Stade Yves Du Manoir, Montpellier
Montpellier climb into the play-off places with a well-deserved win.
The hosts led 11-6 at half time with Renge Ranger and FranÃ§ois Trinh-Duc particularly impressive and Timoci Nagusa scoring the first try.
Three more tries were score in the second half as UBB fought back but full-back Pierre Berard's try - after kick-pass from Trinh-Duc and an offload from Ranger - was enough to give Montpellier some breathing room.
Tries: Nagusa, Berard
Pens: Escande 5, Paillaugue
Yellow card: Escande
Tries: Le Bourhis, Penalty try
Cons: Bernard, Saubusse
Pens: Bernard 3
Montpellier: 15 Pierre Berard, 14 Rene Ranger, 13 Anthony Tuitavake, 12 Robert Ebersohn, 11 Timoci Nagusa, 10 Francois Trinh-Duc, 9 Eric Escande, 8 John Beattie, 7 Mamuka Gorgodze, 6 Alexandre Bias, 5 Thibaut Privat, 4 Robins Tchale Watchou, 3 Maximiliano Bustos, 2 Charles Geli, 1 Mikheil Nariashvili,
Replacements: 16 Mickael Ivaldi, 17 Yvan Watremez, 18 Sitaleki Timani, 19 Alex Tulou, 20 Benoit Paillaugue, 21 Lucas Dupont, 22 Anthony Floch, 23 Paea Faanunu.
Bordeaux-BÃ¨gles: 15 Darly Domvo, 14 Metuisela Talebula, 13 Felix le Bourhis, 12 Thibault Lacroix, 11 Blair Connor, 10 Pierre Bernard, 9 Heini Adams, 8 Matthew Clarkin, 7 Hugh Chalmers, 6 Louis Madaule, 5 Alikisio Fakate, 4 Jandre Marais, 3 Albert Toetu, 2 Wayne Avei, 1 Jean-Batiste Poux.
Replacements: 16 Benat Auzqui, 17 Jefferson Poirot, 18 Cameron Treloar, 19 Taiasina Tuifua, 20 Emmanuel Saubusse, 21 Romain Lonca, 22 Charles Brousse, 23 Silviu Florea.
Referee: Patrick Pechambert
CA Brive-CorrÃ¨ze 23-10 Rugby Club Toulonnais
Stade AmÃ©dÃ©e-Domenech, Brive-la-Gaillarde
Another big club bites the dust! Once again Toulon's inability to travel has raised doubts about their chances of claiming the title that they have invested so heavily in chasing.
An ultra-motivated Brive outfit raced to a 20-4 half-time lead thanks to their dominant pack and the accurate boot of full-