Wales star Liam Williams out of Rugby World Cup semi-final against South Africa

The Wales and Lions full-back has picked up an ankle injury in training and his tournament looks over

Liam Williams is out of Wales’ Rugby World Cup semi-final against South Africa in Yokohama on Sunday in what is a hammer blow to Warren Gatland and his team.

The Lions Test full-back is understood to have sustained an ankle injury in training on Wednsday.

The injury is so bad Williams is said to be on crutches and it appears his tournament is also over.

There has been increasing pessimism about whether the 65-times capped player would be fit to face the Springboks.

And it seems unlikely he will make the World Cup final either, should Wales beat South Africa and face either England or New Zealand.

The news comes as a devastating setback to Williams himself, Gatland and Welsh supporters, with the star full-back a firm fans' favourite and pivotal figure in the side.

Wales have another Lions Test No. 15 in reserve in Leigh Halfpenny, but Williams has been a key player for them over the last year with his counter-attacking and pace from the back.

He has featured in four out of his team’s five games at this World Cup and starred in the victory over Fiji.

But his ankle injury is being seen as significant and Halfpenny seems set to step in as replacement.

Halfpenny himself is no stranger to the big global-tournament stage, having played at full-back when Wales faced France in the 2011 semi-final.