The boot of Benjamin Urdapilleta made the difference as Castres Olympique beat Montpellier 29-13 to claim a surprise French Top 14 rugby title on Saturday.
Australian fullback Jesse Mogg scored a try for Montpellier, but the star-studded team who finished the regular season in top spot weren't able to overcome a 6-19 half-time deficit.
Urdapilleta slotted home five penalties and converted tries by former Western Force Super Rugby forward Steve Mafi and Julien Dumora to give Castres their first title since 2013.
Castres, who finished the season in sixth place, had to go through a playoff tie on their way to the final.
On Saturday they got the better of a Montpellier side featuring former Wallabies and Brumbies back Joe Tomane, and former Super Rugby stars Nemani Nadolo, Aaron Cruden, Bismarck du Plessis and Jannie du Plessis.
