Tottenham defender Ben Davies will miss Wales' World Cup qualifier against Serbia on Saturday.
The Spurs left-back suffered an ankle injury during the 1-0 Champions League defeat to Bayer Leverkusen last week, which ruled him out of Sunday's north London derby.
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, and his absence is a big blow to the Dragons.
Sunderland full-back Adam Matthews, who is on loan at Bristol City, has been called into the squad as his replacement.