Wales have a new back-three injury worry as they prepare to face England in the Six Nations at Twickenham on Saturday, 7 March.
Hallam Amos failed a late fitness test before Cardiff Blues took on Edinburgh in the Pro14 in Edinburgh on Friday.
Josh Adams is out of the tournament and fellow wing George North is undergoing head injury protocols after he was forced off in defeat by France.
Amos returned for Blues last weekend as they beat Benetton.
He had not played since damaging ankle ligaments in January, but was called up by Wales boss Wayne Pivac before returning to regional action.
However, Amos limped off in the dying moments against Benetton on 23 February.
New Scarlets signing Liam Williams has yet to play since suffering an ankle injury at the 2019 World Cup in Japan.
Amos and Williams can play wing or full-back.
Williams has been kept in the Wales camp this weekend despite his lack of game time and not released for Scarlets' Saturday game against Munster.
Amos had been released to Blues and was initially named in Blues' starting XV for the match at Murrayfield, but Dan Fish took his place.
Wales and Blues are also without wing Owen Lane, who suffered a "significant hamstring injury" in training ahead of the Six Nations.
Against France, Wales' injuries prompted Nick Tompkins switching from centre to wing.
Pivac has uncapped teenage wing Louis Rees-Zammit, of Gloucester, Scarlets' Johnny McNicholl and Leicester's Jonah Holmes among his back-three options along with Leigh Halfpenny. McNicholl, Holmes and Halfpenny can also play full-back.
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