Leinster have suffered a double setback after second-row James Ryan and wing Adam Byrne were ruled out for several weeks due to injury.
Head coach Leo Cullen issued the injury update as the team continues preparations for a return to action, against Munster at Aviva Stadium on August 22.
Ryan suffered a shoulder injury in training before the recent break and had a procedure to address the issue. He will be out of action for up to 10-12 weeks.
Byrne meanwhile sustained a hamstring injury and is due to have a procedure this week, which rules him out for up to 12 weeks.
In other injury news, Peter Dooley is rehabilitating a shoulder injury and will aim to return to training in the next two weeks.
Vakh Abdaladze suffered a recurrence of his back injury and is seeking further opinion before a course of rehabilitation is decided upon, while James Lowe returned to training last week having followed all government health advice and guidelines upon his arrival back into the country from New Zealand.
Finally, Dan Leavy is continuing to integrate gradually into rugby training after a significant multi-ligament knee injury.