Ireland internationals Rob Kearney and Jamie Heaslip will be absent for Leinster for "a number of weeks", head coach Leo Cullen confirmed on Friday.
Speaking to the media at the RDS Arena, Cullen said that both players would miss their Champions Cup quarter-final clash with Wasps due to knee and back injuries.
Fullback Kearney missed Ireland's final Six Nations game with England through a knee injury picked up in training, while Heaslip was a late withdrawal ahead of that final fixture with a lower back complaint.
Both players have undergone minor surgery this week.
"It's hard to be definitive with timelines," Cullen said when asked about how long Heaslip would be out of action.
"Jamie [Heaslip] just had a procedure done on his back this morning. He had disc issues. Obviously they come on quite quickly.
"He trained the week of the England game, pulled out in the warm up, at the very end I believe. He had a bit of discomfort at the start of the week, so he saw a specialist.
"He saw somebody again yesterday afternoon so he was straight in and had a procedure done this morning. It obviously rules him out of the next number of weeks. When we get a report we'll find out how long that will be. It sounds like they're reasonably standard procedures.
"Rob [Kearney] had an issue with his knee. It happened in training the week of the England game.
"He had a procedure done during the week after seeing a specialist on Tuesday. That's probably four to six weeks. We'll see how he comes through that."
Leinster face the Cardiff Blues in Dublin on Saturday, live on Sky Sports 2 HD, before all attentions turn to their European Cup clash with Aviva Premiership leaders Wasps.
"It's definitely a loss, if you think of what's coming up," Cullen added. "But that's the nature of the business we're in. It's another chance for guys to come in.
"We've used a good number of players so far this season. The experience that they built up, over the course of last season as well, hopefully will stand to the group.
"It's never an ideal time [to be missing players through injury], particularly as you're very much into the business end of the season now. We'll see how they are and see how they come through and try and have them back as quickly as possible."
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