Wales coach Warren Gatland is to delay his team announcement for next Saturday's RBS 6 Nations opener against England at Twickenham.
It follows a two-week ban handed out to Ospreys full-back Lee Byrne on Friday.
Byrne is considering whether or not to appeal a suspension after he admitted a misconduct charge brought by European Rugby Cup disciplinary officer Roger O'Connor. It followed his brief appearance as an illegal 16th player during Ospreys' Heineken Cup victory over Leicester last weekend.
Byrne was expected to start at Twickenham, and Gatland has now decided to reschedule Sunday's planned announcement.
Byrne has until Monday to lodge any protest.
In a statement, the Welsh Rugby Union said: "Head coach Warren Gatland had intended to name his side on Sunday January 31, but will now wait pending a possible appeal by Lee Byrne of an independent disciplinary committee decision to ban the player for a period of two weeks.
"The ban was imposed on Friday January 29 at a hearing in Dublin after misconduct complaints were brought by Heineken Cup tournament organiser ERC relating to the round-six match of the competition between Ospreys and Leicester Tigers the previous week.
"Byrne has a period of 72 hours from the time the decision was made to lodge an appeal and is currently taking advice while based at national-team headquarters, the WRU national centre of excellence at the Vale Resort in Hensol.
"A new time and date for the team announcement will be issued when appropriate and no further comment will be made on the subject at this stage."