
Fears are growing that Robbie Henshaw's Rugby World Cup is in jeopardy due to a hamstring injury.
Ulster's Will Addison has been taken out of the starting XV for the province's pre-season friendly against Glasgow Warriors, with James Hume's inclusion confirmed five minutes before kick-off.
The versatile former Sale Sharks back will be called up if Henshaw is ruled out.
The Athlone native, who was a key man in Ireland's 2015 campaign, is in line to start against Scotland in a week's time but speculation is mounting that he is now a serious doubt for that clash and the remaing games of the pool campaign.
It would be a bitter blow to the 26-year-old who has endured a tough couple of seasons with injury.
Garry Ringrose would start alongside Bundee Aki if Henshaw is ruled out.
Joe Schmidt is scheduled to conduct his first press conference in Japan at the team's base in Chiba overnight.