Leinster wing Luke Fitzgerald will miss the Heineken Cup final against Ulster as he needs surgery on a neck problem.
A statement from Leinster on Friday said that Fitzgerald would undergo surgery in the "coming weeks".
The injury will also rule Fitzgerald out of contention for Ireland's summer tour of New Zealand.
"To lose a player of Luke's pedigree is a massive blow, not just for the team and supporters, but also the player," said Leinster coach Joe Schmidt.
It is the latest injury blow for Fitzgerald, who was forced out of Ireland's Six Nations campaign and also suffered a serious knee injury in 2009 which caused him to miss the entire 2010 Six Nations campaign.
Fitzgerald had forced his way back into the Leinster team in the closing stages of this season.
He started in last weekend's Heineken Cup semi-final against Clermont-Auvergne and looked set to feature in the decider against Ulster on 19 May.
"Luke has been in fine form recently and as well as his capabilities on the field, he is a positive and popular presence within the dressing-room," added Leinster coach Schmidt.
"Knowing Luke, he will be determined to overcome this setback and aggressively tackle his rehab to regain full fitness.
"He will continue to benefit from the full support of Leinster Rugby and the IRFU during that time frame."