Racing 92's France hooker Camille Chat said on Monday he will be sidelined for up to two months with a leg injury suffered in the weekend's European Champions Cup loss to Bordeaux-Begles.
Chat, 25, who won the last of his 33 Test appearances during the Six Nations, was helped off the pitch after 34 seconds of Sunday's semi-final defeat at Stade Chaban-Delmas.
"Fractured tibia. Six to eight weeks out. Thanks for your messages of support," he posted on Instagram.
Chat could miss the remainder of his club's regular season Top 14 games including this Saturday's Parisian derby with Stade Francais.
Racing, champions in 2016, are third in the Top 14 table, four points behind La Rochelle in second place, the final semi-final spot.
Chat could return in time for the league play off on the weekend of June 11-13.
Racing are also without Scotland flyhalf Finn Russell, who is suspended, as well as the injured Teddy Thomas, Bernard le Roux, Virimi Vakatawa, Simon Zebo and Henry Chavancy.
Les Bleus are set to tour Australia in the summer with the first Test scheduled on 3 July, a week after the Top 14 final.