Biarritz - South African prop Eugene Van Staden returned to French club rugby for a second spell on Tuesday when Top 14 tailenders Biarritz signed him as a replacement for the retired Eduard Coetzee.
Van Staden, 31, played for Montpellier from 2007-2010 before returning to South Africa to play for the Sharks.
Biarritz, five-time French champions and twice European Cup finalists, hope to have him able to play in Saturday's European Cup match with Saracens and have sent his file to the tournament organisers, European Rugby Cup (ERC), so they declare him eligible.
Coetzee had announced on Monday he was retiring after being told by doctors that he had taken too many blows to the head.
The 32-year-old South African-born naturalised Frenchman-- who has been at Biarritz since 2007 - said he had sought advice from several specialists before taking the decision.