Ireland captain Johnny Sexton looks set to miss the rest of this season after suffering a groin injury.
Sexton was hurt during the closing stages of Ireland's Six Nations title and Grand Slam-clinching victory over England in Dublin nine days ago.
Sexton's provincial team Leinster say that the 37-year-old will undergo a procedure on the injury on Tuesday.
The fly-half is likely to miss the remainder of Leinster's Champions Cup and United Rugby Championship campaign.
"Johnny Sexton will see a specialist on Tuesday and have a procedure on the groin injury picked up in Ireland's Six Nations game against England, which will likely keep him sidelined for the remainder of the Leinster Rugby season," read an update from Leinster Rugby.
It means that Sexton, who will retire after the World Cup later this year, has probably played his final game for Leinster.
Ireland's opening World Cup warm-up Test, meanwhile, is against Italy in Dublin on 5 August.
Leinster are chasing a Heineken Champions Cup and United Rugby Championship trophy double.
They host Ulster in the Champions Cup round of 16 on Saturday, with the winners facing a home quarter-final against Leicester or Edinburgh a week later.
Leinster are runaway leaders of the URC, and will contest the play-offs next month as clear title favourites.