English referee Wayne Barnes has been appointed to take charge of the key RBS Six Nations clash between Wales and Ireland in Cardiff on March 14th.
Barnes will replace Australia's Steve Walsh, who World Rugby announced had withdrawn from the game because of business commitments.
In a further change ahead of the Millennium Stadium encounter, New Zealand's Chris Pollock has been replaced as one of the assistant referees by Frenchman Jerome Garces.
Barnes had initially been appointed as an assistant official for Italy versus France on March 15th, but Welshman Nigel Owens will now take over from him in that role.
Barnes refereed Ireland's win over France in round two of the competition at the Aviva. He handed French lock Pascal Pape a yellow card in that game for his knee on Jamie Heaslip which cracked three vertebrate in the Leinster captain's back. Pape was subsequently handed a 10-week ban for the incident.
