Toulon on Friday announced the signing of Cheslin Kolbe, the South African World Cup winner moving from rival French Top 14 side Toulouse.
Kolbe, 27, had two years still to run on his contract with five-time European champions Toulouse.
The star winger, who is currently in action in the Rugby Championship with the Springboks, joins Toulon on a three-year deal.
"RCT (Toulon) are very happy to announce the arrival....of the world, European and French champion, Cheslin Kolbe," the player's new employers posted on Twitter.
Kolbe wrote also on Twitter that the time had come to say "au revoir" to "one of the greatest chapters of all time".
"I hope you understand my decision to move on to Toulon was not easy," he told his now ex-Toulouse teammates and the club's fanbase.
"I will forever be grateful for everything I have learned and experienced with Stade Toulousian, the lessons learnt and the memories made stretch far beyond the rugby field."
Kolbe won the French Top 14 in 2019 and again last season when Toulouse also won the Champions Cup.
The 2016 Olympic bronze medallist claimed nine tries in 23 games but had a 13-match streak without scoring last term.
South Africa's next fixture in the Rugby Championship is against Australia in Queensland on September 12.
The Top 14 season begins on September 4 but Kolbe is unlikely to feature until the end of his Test commitments in October.
While common in football, transfers like Kolbe's are still a rarity in rugby where players traditionally see out the length of their contracts.
To secure Kolbe, Toulon had to pay Toulouse an unspecified fee.