Clermont's 34-year-old flanker Gerhard Vosloo has signed a contract with Toulon for next season on a potential two-year deal.
Vosloo has initially signed for one season with the option of another.
Toulon will be Vosloo's third French club since joining Brive in 2008 from his native South Africa, where he played for the Lions.
He moved to Clermont in 2011 and has been in outstanding form over the last few seasons for les Jaunards.
Vosloo is the second new arrival confirmed by Toulon on Monday, following the announcement that scrum-half Éric Escande had signed from Montpellier on a two-year deal.