Ben Davies will miss Wales' World Cup qualifier against Serbia on Saturday.
The Tottenham defender suffered an ankle injury during the 1-0 Champions League defeat to Bayer Leverkusen last week.
Davies missed the 1-1 Premier League draw at Arsenal on Sunday and his absence is a big blow to Wales.
The 23-year-old was one of Wales' best performers at Euro 2016 last summer as Chris Coleman's side reached the semi-finals in France.