Ireland flanker Peter O'Mahony has been ruled out of the Rugby World Cup with a knee injury.
O'Mahony suffered the injury in Ireland's final Pool D game against France in Cardiff on Sunday.
Joe Schmidt's side won the match 24-9 to secure top spot in the pool and a potentially easier route to the final - but the win came at a substantial cost with O'Mahony, Johnny Sexton and Paul O'Connell all leaving the field injured.
Schmidt had hoped O'Mahony would be available for Sunday's quarter-final against Argentina but Ireland team manager Mick Kearney confirmed on Monday morning that O'Mahony's injury was more serious than first thought.
Leinster's Rhys Ruddock has been called up as a replacement for O'Mahony and has already joined up with the rest of the squad in Cardiff.
Kearney also said both O'Connell and Sexton are awaiting scans on hamstring and groin injuries respectively and that there would be a further update later on Monday - although Sexton's condition was described as "hopeful" on the Irish Rugby twitter account.
"Peter O'Mahony has suffered a knee ligament injury and is returning to Dublin today for specialist opinion and will take no further part in the tournament," said Kearney.
"Paul O'Connell appears to have suffered a significant hamstring injury and was hospitalised overnight, he's having scans later today to clarify the extent of the injury.
"Johnny Sexton suffered a groin injury, initial clinical assessment is encouraging and we await scanning later today.
"After an incredibly physical encounter a host of players are reporting bumps and soreness and will have to be managed, but nothing more serious than that.
"As soon as we have more clarity on the injury front we will be in a position to make decisions on replacement players.
"At the moment definitively only Peter O'Mahony has been ruled out.
"Paul was in hospital overnight and he was obviously very sore. In relation to Jared Payne's replacement that's similar too.
"I'd be pretty sure that a decision would be made later today. The coaches did meet this morning and discuss a number of different options."