There is no choice for us
Title favourites Clermont are facing a dangerous trip to Perpignan in the Top 14 on Friday, with Toulon, who are level with them atop the table, travelling to Paris to take on Stade Francais on Saturday.
The Auvergne side were in superb form last weekend when they trounced Racing Metro 47-14 at home, but the club injury list makes sorry reading ahead of the Perpignan trip.
The biggest loss could be at scrum-half where Morgan Parra is facing up to 12 weeks on the sidelines after damaging knee ligaments playing for France against South Africa last Saturday.
Clermont will also be without centre Benson Stanley, who has a pulled stomach muscle with Wesley Fofana, Aurelien Rougerie, Lee Byrne and Sitiveni Sivivatu all uncertain due to injury.
On the plus side Fiji have cleared winger Napolioni Nalaga for club duty and he will be able to lineup against Stade. Scottish lock Nathan Hines is also back in the reckoning
Perpignan, coming off a 15-9 loss to Toulon, also have injury concerns surrounding back rower Bertrand Guiry (calf muscle), prop Sebastien Taofifenua (left ankle) and full-back Richard Haughton (groin).
International winger Sofiane Guitoune, who was a standout performer for France against Tonga and South Africa, said Perpignan needed a win on Friday if they were to harbour realistic hopes of reaching the playoffs.
"There is no choice for us. Either we defeat Clermont and we are into the top six in the table by the end of the first half of the season.
"Or we lose and it's the slippery slope for us after that."
European champions Toulon have blown hot and cold since the start of the season, although Springboks lock Bakkies Botha believes there is no big problem at the Mediterranean club.
"I am not unduly bothered about this (inconsistency}," he said.
"We saw it again against Perpignan -- it's all a matter of getting the little details right. We have got to correct the mistakes we are making.
"But we have the players that can do this. In our squad we have several players who have the experience to get this done."
Botha also said that he expected a close match on Saturday in Paris against a side who lost 45-23 at Bordeaux last weekend.
"When you play for Toulon, you know what to expect. There is a lot of pressure on us because everyone wants to beat us. That's normal and we accept it."
Third-placed Toulouse travel to Grenoble with coach Guy Noves having given the week off to his international players Thierry Dusautoir, Yoann Maestri, Yoann Huget and Jean-Marc Doussain, who all played for France at the weekend.
Explaining his decision, Noves said: "I heard that the (international) players were really exhausted. We have to give them the time to recover properly.
"They need to be fresh and ready not only going into the international matches, but also afterwards. Especially as they have just been playing against the two best sides in the world."
In other matches, defending champion Castres are at home to Bayonne, Racing Metro host Montpellier, bottom dogs Biarritz welcome Bordeaux and Oyonnax are at home to Brive.
Top 14 fixtures (kick-off times all GMT)
Friday, November 29:
Perpignan v Clermont (1945)
Saturday, November 30:
Stade Francais v Toulon (13.55)
Biarritz v Bordeaux (17.30)
Castres v Bayonne (17.30)
Oyonnax v Brive (17.30)
Racing-Metro v Montpellier (17.30)
Grenoble v Toulouse (19.35)