Racing 92 trio Dan Carter, Joe Rokocoko and Juan Imhoff have been asked to appear before the French Anti-Doping Agency for the use of corticosteroids.
Three South Africans tasted defeat on Sunday as Toulon suffered a 30-6 loss to Clermont at the Stade Marcel-Michelin.
The former Sharks scrumhalf scored Grenoble's third try in their French Top 14 match against Brive.
Frans Steyn contributed 13 points with the boot as Jake White's Montpellier beat Bordeaux-Bègles in the French Top 14 on Friday night.
Former Springbok wing Cornal Hendricks has left French club Toulon without getting onto the field.
Toulon fullback Leigh Halfpenny was furious when music played just as he was about to kick a conversion, which went wide.
Racing 92 will “initiate several legal proceedings aimed at enforcing its rights and redressing the harm done to the club” by Johan Goosen.
Utility back Johan Goosen has been linked with a move to Gloucester less than a week after it came to light that he had retired.
Springbok and Racing 92 utility back Johan Goosen has retired from professional rugby.
Toulon v La Rochelle
Toulouse v Pau
Grenoble v Stade Francais
Castres v Montpellier
The make-up of the South African squads that will compete in the Africa 1 and Africa 2 conferences in 2017.
The make-up of the squads that will compete in the New Zealand conference in 2017.
The make-up of the squads that will compete in the Australian conference in 2017.
Before you make your SuperBru picks for this weekend's Test match, take a look at the SA Rugby magazine team's predictions.
World Rugby chats with USA coach John Mitchell as part of its #MondayMotivation series.View all videos