Kumamoto - France suffered two more injury blows to their Rugby World Cup campaign on Thursday when hooker Peato Mauvaka and fullback Thomas Ramos were both ruled out of the rest of the tournament.
Rumours of the seriousness of their injuries were first aired by RMC Sport and later confirmed to AFP by a source close to the team.
France have already lost centre Wesley Fofana and prop Demba Bamba.
Ramos, who injured his right ankle in the 33-9 win over the USA on Wednesday, will be replaced by La Rochelle fullback Vincent Rattez whose two previous Test appearances came as a substitute on the 2017 tour to South Africa.
Mauvaka, the third hooker behind captain Guilhem Guirado and Camille Chat, figured in neither game and was injured in training.
He is replaced by Toulon's Christopher Tolofua who played seven Tests between 2012 and 2017.
France have won both of their matches, against Argentina and the USA, and are one point behind leaders England in Pool C.
The French meet Tonga in Kumamoto on Sunday.