James O’Connor could be in line for his Top 14 return this week, named in Toulon’s 27-man squad to face Stade Francais.
O’Connor, Drew Mitchell and Ben Barba were among 11 backs named in the travelling squad, while Liam Gill was named in the forwards on Saturday, Australian time.
The former Wallabies back returned to training for the first time since being fined for cocaine possession in Paris last month.
Toulon will take on Stade on Sunday, with their season on the line after a tumultuous week, in which coach MIke Ford was told his tenure would be over at the end of the season.
Sitaleki Timani will start in the second row for Clermont against Racing 92 this weekend, as the Paris side resumes its campaign after two weeks of merger controversy.
Mike Harris will come off the bench for Lyon against Bayonne, likely to replace starting flyhalf Freddie Michalak in the clash.
Adam Ashley-Cooper (wing) and Luke Jones (second row) will both run on for Bordeaux against Toulouse.
Teams for Montpellier’s clash with Brive are yet to be named, though the destination of Montpellier coach Jake White has been confirmed this week.
The former Brumbies mentor will move to Japan to take the reins of Toyota Verblitz.
Former Brumbies halfback Michael Dowsett has had his UK deal made permanent in Worcester.
"Michael has shown tremendous professionalism since joining the club," said Worcester rugby director Gary Gold.
"He provides important competition in the half back position and he's a hungry, enthusiastic individual who drives standards across the board."
Dowsett featured for New Zealand's Southland in the 2016 Mitre 10 Cup competition, but now the 25-year-old is intent on carving a long-term stint at Sixways.
"I've enjoyed my short time in Worcester so far and I'm looking forward to the future," Dowsett said.
"Hopefully I can take my opportunities when they come along and help the team push on."
Kurtley Beale will line up at fullback for Wasps against Dowsett’s Worcester this weekend.
James Horwill will start for Harlequins against Newcastle, as the London side looks to stay in touch with the top echelon of the competition.
Ben Tapuai will play at 12 for Bath against the reigning champion Saracens.