Double Rugby World Cup winner Ma'a Nonu is a doubt for Toulon's Top 14 trip to Castres this weekend after undergoing surgery for appendicitis, his French club said on Tuesday.
Former New Zealand centre Nonu, 39, returned to Stade Mayol on a short-term deal this season and faces a race to be fit to feature in Saturday's final game of the regular season.
At Stade Pierre-Fabre Toulon need at least a draw and to better Stade Francais' result at Bayonne to claim a play-off spot.
"The operation went well," Toulon said.
"The All Black double world champion will be sidelined for many days," they added.
Nonu, who lifted the Webb Ellis trophy in 2011 and four years later, left Toulon in 2018 before rejoining former franchise the Blues and then signing for US side San Diego Legion.
He has played 16 games since arriving back on the Mediterranean coast in November, with Toulon in seventh place in the table and just points difference separating the four-time champions and the Parisians in sixth spot.