Top 14 high-flyers slump to defeat
Log leaders Clermont slumped to their second defeat of the season on Sunday with their 9-14 loss to defending champions Stade Francais allowing the Paris giants to escape the bottom three.
Racing 92, who also had also suffered just one defeat before this weekend's round of matches, were thrashed 8-32 by Castres in Sunday's earlier game.
In Paris Stade scored the only try of the game through South African flank Jono Ross in the 14th minute as the hosts swept into a 11-0 half-time lead beneath bright sunshine at their Stade Jean-Bouin home.
Clermont had to settle for three second-half penalties from Brock James (two) and Camille Lopez for their points with the team forced to wait until the 55th minute before opening their account.
Stade welcomed back inspirational skipper Sergio Parisse as coach Gonzalo Quesado looked to the Italian to ease an injury crisis which had sidelined fellow back row forwards Antoine Burban, Raphael Lakafia and Sekou Macalou.
Centre Jonathan Danty also enjoyed a solid afternoon and looked to have set up a second try for Jeremy Sinzelle but the score was ruled out for a forward pass.
Castres bucked a three-match losing streak with a much-needed bonus-point win over high fliers Racing 92.
The home side led 7-3 at the interval after a try by Alexandre Bias converted by Rory Kockott, the South African-born France international scrum-half playing his 100th Top 14 match.
Racing paid for their ill-discipline in the second-half, with yellow cards for Ross Filipo and Henry Chavency offering Castres numerical supremacy in the third quarter.
And Castres did not let the opportunity pass, scoring three tries during the sin binnings through France-qualified New Zealand No.8 Alex Tulou (two) and ex-Toulon wing David Smith, Kockott nailing a penalty and two conversions.
Louis Dupichot crossed for a Racing try in the 64th minute before Castres had the final word with a magnificent touchdown from France wing Remy Grosso after some slick handling tore holes in Racing's porous midfield defence.
In Saturday's action, Australian flyhalf Quade Cooper enjoyed the ideal introduction to the Top 14 as he steered Toulon to a 52-8 thrashing of Montpellier.
Toulouse would not be outdone as they also ran in eight tries to go second as they blitzed Grenoble 52-12. La Rochelle put Oyonnax to the sword, 38-3, while Pau edged Agen 33-31 and Brive notched up an impressive 16-3 home win over Bordeaux-Begles.
Top 14 Round Eight results:
Toulon 52 Montpellier 8
La Rochelle 38 Oyonnax 3
Pau 33 Agen 31
Brive 16 Bordeaux-Begles 3
Toulouse 52 Grenoble 12
Stade Francais 14 Clermont 9
Castres 32 Racing 92 8
Agence France-Presse