Ireland captain Johnny Sexton looks likely to miss the rest of the European season after suffering a groin injury in the win against England that sealed the Six Nations title earlier this month.
Sexton was hurt during the closing stages of the match in Dublin on 18 March, which clinched Ireland's first Grand Slam since 2018.
Sexton's provincial team, Leinster, said in a statement on Monday the 37-year-old flyhalf would undergo a procedure the following day.
"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," Leinster said.
It means Sexton, who will retire after the World Cup in France later this year, has probably played his final game for Leinster.
Ireland's opening World Cup warm-up test is against Italy in Dublin on5 August.
Leinster are chasing a Champions Cup and United Rugby Championship double.
They host Irish rivals Ulster in the Champions Cup round of 16 on Saturday, with the winners facing a home quarterfinal against Leicester or Edinburgh a week later.
Leinster are runaway leaders of the URC, and will contest the playoffs next month as clear title favourites.