Warren Gatland was seemingly dealt a Six Nations blow, as Scarlets fly-half Sam Costelow was forced off injured just days before the Wales coach names his squad.

The 18-cap fly-half departed just minutes into the Scarlets' Challenge Cup clash with Gloucester at Kingsholm, clutching his shoulder as he was replaced by Ioan Nicholas.

Costelow, having featured regularly for Wales in the past year, would have been almost certain to be named in Gatland's Six Nations squad on Monday.

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However, an injury could derail his involvement.

On his 24th birthday, Costelow was the relatively experienced head in a youthful backline at Kingsholm. However, his involvement didn't last long.

And, as he now waits to learn the extent of his injury, Gatland will also be sweating on the fitness of Costelow.

The Anglo-Welsh clash between Gloucester and the Scarlets was already notable for the absence of Gareth Anscombe, who missed the game because of a knee issue.

Both were a part of Gatland's recent autumn squad and it could leave the Wales coach scratching around for fly-halves if both are struggling to make Monday's squad.

Ospreys' pivot Dan Edwards is likely to be in the mix, having been in fine form for Mark Jones' side this season. He was invited to train with Wales in the autumn, but was injured at the time.

Harlequins fly-half Jarrod Evans could come into the frame. Wales' coaches are understood to be keeping an eye on him, but are likely to put faith in Welsh-based fly-halves that they have invested time in - although injuries could quickly change that thinking.

Ben Thomas, although he spent the autumn in his favoured position of inside centre, did wear the 10 jersey on the summer tour of Australia last year.

Gatland's Six Nations squad on Monday carries an extra sense of importance after a winless 2024. The Welsh Rugby Union have challenged Gatland to improve results on the field, with his future to be assessed again after the tournament.