Daniel James and Aaron Ramsey have dropped out of the Wales squad for games against England and Belgium.
Leeds United winger James faces four to six weeks on the sidelines with an ankle problem and Ramsey, who has not played for Wales for 13 months due to injury troubles, missed his Mexican club Pumas UNAM's weekend game after reporting a muscular issue.
Cardiff pair Isaak Davies and Rubin Colwill have been called into Craig Bellamy's squad for the Wembley friendly with England on Thursday and the World Cup qualifier against Belgium in Cardiff four days later.
The 86-times capped Ramsey signed for Pumas in the summer and returned from a five-month lay-off in August following hamstring surgery.
Wales are third in Group J with 10 points through five games, one behind leaders North Macedonia.
Information from PA was used in this report.
