Wales and Cardiff Blues wing Hallam Amos will miss the rest of the season with a knee injury that needs surgery.
The 25-year-old sustained the injury during the Blues' Pro14 win over Benetton on 23 February.
Amos missed out on selection for Wales' Six Nations squad because of an ankle problem, before replacing the injured Owen Lane.
Fellow Wales and Blues wing Josh Adams will also miss the next three months because of an ankle injury.
Wales have injury concerns in the back three with George North failing a head injury assessment in the defeat against France.
Liam Williams has only just returned to full training after suffering an ankle injury before the World Cup semi-final against South Africa in October 2019.
Uncapped teenage wing Louis Rees Zammit missed Gloucester's match last weekend through illness.
Leigh Halfpenny, Johnny McNicholl and Jonah Holmes are the other back three options.