Sean O'Brien looks set to be on the sidelines for Leinster's Champions Cup semi-final with the Scarlets.
O'Brien has had an injury-hit season with the latest set back coming in the province's shock defeat to Benetton last Saturday where the 31-year-old only lasted 40 minutes.
The openside flanker injured his shoulder in the 15-17 defeat and despite having been deemed as having a 50-50 chance of playing, it now looks unlikely he will feature on Saturday.
According to The42.ie, O'Brien may also require surgery on the injured shoulder, meaning it would rule the player out for a number of weeks.
Injuries have meant O'Brien has only played six times for Leinster this season and also caused him to miss out on Ireland's Grand Slam heroics in the Six Nations.