Scrumhalf Kieran Hardy has been ruled out of Wales' remaining Six Nations games after suffering a hamstring injury, the Welsh Rugby Union announced on Thursday.
Hardy, who scored a try during the Triple Crown-clinching 40-24 victory over England on Saturday, was hurt later in that match.
The 25-year-old will miss Wales' fixtures against Italy and France later this month, and the WRU said he has been released from the squad.
"Kieran has been released from the squad due to a hamstring injury suffered in the game versus England on Saturday," the WRU said.
"He will continue his rehabilitation back at the (PRO14 side) Scarlets."
Scrumhalf Tomos Williams, who picked up a hamstring injury during Wales's opening Six Nations win against Ireland, could be back in the frame for the trip to Rome on 13 March, while head coach Wayne Pivac also has Gareth Davies and Lloyd Williams as scrumhalf options.
Victories over Italy and France would give Wales a second Grand Slam in three seasons.
They are currently five points ahead of France at the top of the Six Nations table, though Les Bleus have a game in hand following the postponement of their clash against Scotland.