Western Force back Chris Tuatara-Morrison has joined Castres on a short-term deal to cover for the injured Sitiveni Sivivatu.
Sivivatu was a star signing for Castres for this season from Clermont, but the former All Black is facing three to four months out with a shoulder injury.
Dipping into the market for some cover before Sivivatu returns later this year, the 2013 Top 14 champions have turned to Tuatara-Morrison for cover.
Tuatara-Morrison comes from a background in rugby league but the 27-year-old has spent the last two years in Perth.
"Chris is a serious player, a good defender and has the necessary attacking skills to fit into the coaches' style," said team manager Matthias Rolland.
"It was important to strengthen the squad quickly in midfield following Sivivatu's injury."