Wins for Toulon and Clermont at the weekend has kept the race for top spot alive in France's Top 14.
Clermont coach Frank Azema has made wholesale changes to his pack for his side's Top 14 encounter against Castres.
Wasps played their final match in High Wycombe, and the London outfit signed off in style with a 44-17 win over Castres.
Wasps aim keep their slender hopes of quarter-final qualification alive with a second victory over Castres.
Castres Olympique host Wasps in the European Rugby Champions Cup on Sunday, live on Sky Sports.
Reigning Top 14 champions Toulon claimed a 27-19 victory against Clermont Auvergne in a clash of the titans on Saturday.
Ireland's joy, England's misery and Wales' woe... Rupert Cox looks at the week in rugby union.
A depleted Toulon team came a cropper at Castres, allowing Clermont Auvergne to take over as new leaders in the Top 14.
The final of the Top 14 will be held at Barcelona’s Nou Camp at the end of the 2015-16 season.
Oyannax caused the biggest upset of the Top 14 season so far on Saturday by clinching victory away at Racing Metro.
Ian Madigan kicked all his side's points as Leinster beat Castres 21-16 in the European Champions Cup.
Leinster will aim to take control of Pool 2 on Sunday as they travel to France for a showdown with Castres (kick-off 1pm).
Jonny Wilkinson, Will Greenwood and Nick Easter analyse all the action from the opening weekend.
Harlequins got their European Rugby Champions Cup campaign off to a winning start with a 25-9 victory over Castres.
Harlequins boss Conor O'Shea is relishing the challenge of taking on Castres in the new European Rugby Champions Cup.
Sky announces the European rugby fixtures being brought to your screens in December.
Clermont sit on top of the Top 14 table as they became the first visiting team to taste victory at Oyonnax this season.
Clermont returned to the summit of the Top 14 standings in style while Castres climbed out of the relegation zone.
Sireli Bobo piled more misery on Castres as La Rochelle cruised home 41-16 to move out of the bottom two.
Montpellier moved to the Top 14 summit with a 43-10 thrashing of 14-man Castres on Friday night.
Rupert Cox shares his highlights from the week's rugby action in his round-up blog...