London: Tottenham Hotspurs defender Ben Davies has been ruled out of Wales' World Cup qualifier against Serbia on Saturday.
Davies suffered an ankle injury during Tottenham's Champions League defeat against Bayer Leverkusen last week.
The 23-year-old missed Tottenham's Premier League draw at Arsenal on Sunday as a result and he won't recover in time to feature for Wales.
Davies was one of Wales' best performers at Euro 2016 as Chris Coleman's side reached the semi-finals in France.
Sunderland full-back Adam Matthews, who is on loan at Championship club Bristol City, has been called into the squad to replace Davies.
"Squad Update: Ben Davies has been withdrawn from the squad through injury and is replaced by Adam Matthews," Wales announced on their official Twitter account.
Matthews, who has won 13 caps for Wales, has been out of favour and missed out on Euro 2016 selection.
Wales are unbeaten in World Cup qualifying but trail Group D leaders Serbia by two points after a disappointing 1-1 home draw against Georgia last month.