Ireland head coach Joe Schmidt will have to plan without Sean O'Brien for the start of the Six Nations campaign after the flanker had a 'small procedure' to treat a hip injury.
O'Brien has been sidelined since Leinster's Champions Cup win against Exeter Chiefs at the Aviva Stadium in mid-December.
Adam Byrne will also have an operation this week on his troublesome knee injury after rehab failed to fix the problem.
A return to play date for Byrne will not be known until after the procedure.
Leo Cullen revealed the news when he announced his team to play Glasgow in the Champions Cup this weekend.
Jordan Larmour has been named in the Leinster team for Sunday's Champions Cup clash with Glasgow at the RDS.
The exciting 20 year old will make his first European start at full back in a back three with new signing James Lowe and Fergus McFadden.
Rob Kearney has been named on the bench. Captain Isa Nacewa returns to replace the injured Garry Ringrose in the centre.
Tadhg Furlong remains in the front row, having completed return to play protocols after a head injury.
Glasgow sit at the bottom of the pool having lost their first four games.
The Scots have left stars Stuart Hogg, Finn Russell, Jonny Gray and Tommy Seymour out of their team.
Leinster XV: Jordan Larmour; Fergus McFadden, Robbie Henshaw, Isa Nacewa (C), James Lowe; Johnny Sexton, Luke McGrath; Jack McGrath, Seán Cronin, Tadhg Furlong; Devin Toner, Scott Fardy, Jordi Murphy, Josh van der Flier, Jck Conan.
Replacements: Bryan Byrne, Cian Healy, Andrew Porter, James Ryan, Dan Leavy, Nick McCarthy, Ross Byrne, Rob Kearney