Pro-dancer Curtis Pritchard will not be returning for the launch of the new series of Dancing with the Stars.
His withdrawal is due to injuries sustained in an incident on St Stephen's night.
The launch of the new series of Dancing with the Stars is due to air on January 6.
A statement from RTÉ said: "Dancing with the Stars pro-dancer Curtis Pritchard was involved in an incident on 26 December 2018.
"As a result of the injuries sustained, he will not have recovered in time for the launch of the new series, which will air 6 January 2019. Dancing with the Stars wish Curtis a speedy recovery."
A replacement is being arranged by the production company, ShinAwiL.
The statement added: "We look forward to welcoming Curtis back when he recovers."
Pritchard's brother, AJ, is a pro dancer on the UK's Strictly Come Dancing.
Media reports suggest the pair were attacked in the UK while out over Christmas.
The celebs set to appear on the third season of Dancing with the Stars include rugby legend Peter Stringer, country music star Cliona Hagan and TV presenters Mairead Ronan and Darren Kennedy.
Jennifer Zamparelli and Nicky Byrne present the new series, which will run for 12-weeks.