Cardiff Blues centre Jamie Roberts has been ruled out for the remainder of the season with a knee injury.
The 25-year-old has damaged his medial ligament and will require surgery to correct the problem.
"With the fantastic help from the medical staff at the Blues and Welsh Rugby Union, I was able to rehab my knee well enough to get me through a handful of games for the Blues and the successful Grand Slam Six Nations campaign with Wales," said Roberts.
"However, following my injury in the match against Glasgow on Friday night I've been advised by the knee surgeon that my knee is now not stable enough to continue playing and potentially risk further injury to the knee.
"It will mean a minimum of roughly six months away from the playing field."
Dafydd Hewitt or Gavin Evans are expected to replace Roberts in the Cardiff starting lineup this weekend.
