Ireland hooker Sean Cronin will miss the Six Nations after Leinster confirmed he will be out for 10 weeks with a hamstring injury.
The 31-year-old, who has 56 caps, has established himself as an impact player off the bench for Ireland in his role as back-up to captain Rory Best.
Cronin suffered the injury during Leinster’s 70-6 thrashing of Zebre in the PRO12 on January 6.
Leinster coach Stuart Lancaster told The42.ie on Monday: “It’s quite a significant hamstring injury.
“It’s a real shame for him as he’s actually playing great rugby, but it’s a good opportunity for us to get him right and make sure we don’t get a recurrence of this because it must be hugely frustrating for him.
“He’s got himself into great form and now he’ll miss the Six Nations. He went to push off and accelerate around the corner and saw it go. He’s deeply disappointed but he’ll be back a better player.”
Cronin’s injury means his Leinster team-mate James Treacy is likely to be given the opportunity to add to the maiden cap he earned during Ireland’s victory over Canada on November 12.
Treacy has moved ahead of Richardt Strauss in the pecking order for Leinster, while Munster’s Niall Scannell is also likely to be considered by Joe Schmidt.
Ireland's Six Nations campaign begins against Scotland at Murrayfield on February 4.
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