Toulon were dealt a big blow in the build-up to Saturday's trip to Exeter Chiefs with the news that former England prop Andrew Sheridan could be forced to retire.
The 34-year-old injured his neck during a 15-9 win against Perpignan last month. Toulon head coach Bernard Laporte admitted that the former Bristol and Sale player may have to call time on his career.
"Andrew is out for a month and possibly forever," Laporte said. "He has always had a problem between his neck and his shoulder. The surgeon has told him that it's not necessary to have a new operation.
"He will now have a month of complete rest and if the pain doesn't go away, then he will have to stop playing rugby."
Sheridan's absence was keenly felt last weekend as Toulon struggled up front and crashed to a 23-0 defeat in Paris against Stade Français, their heaviest loss of the season.
Toulon president Mourad Boudjellal criticised his side's scrum after the defeat, slamming it as their worst in the Top 14. France centre Mathieu Bastareaud admitted they did not deserve to win.
"23-0 – there is nothing more to say," said Bastareaud. "Big congratulations to Stade Français, they played very well.
"Our opponents were very aggressive, they showed us what rugby really is. We tried, but we failed, we were heckled. The way we played, we couldn't possibly win."
Laporte chose to rest some of his front-line players for the match, with England legend Jonny Wilkinson and former London Irish duo Delon and Steffon Armitage not making the trip to Paris at all.
However, the strength of Toulon's squad was still evident as World Cup winners Bryan Habana, Bakkies Botha and Ali Williams all featured, as well as Michael Claassens, Frédéric Michalak, Martin Castrogiovanni, Carl Hayman, Matt Giteau, Drew Mitchell and Johann van Niekerk.
Laporte has more depth to call on than most coaches, but he needs a much-improved display against Exeter this weekend.
Toulon announced their travelling squad on Thursday. Delon Armitage misses out because of a sore shoulder, but Bastareaud has shaken off a knee knock and is on his way to Sandy Park.
Toulon (from): Backs: Bastareaud, Claassens, Giteau, Habana, Mermoz, Michalak, Mitchell, Palisson Tillous-Borde, Wilkinson, Wulf. Forwards: S Armitage, Botha, Bruni, Burden, Castrogiovanni, Chiocci, Fresia, Gunther, Hayman, Masoe, Orioli, J Smith, Suta, Williams.