Ireland hooker Sean Cronin is expected to miss the entirety of the upcoming Six Nations after being ruled out of action for 10 weeks with a hamstring injury.

Club side Leinster confirmed on Monday that the 30-year-old's injury, picked up in the 70-6 victory over Zebre earlier this month, was far worse than initially expected.

Cronin underwent a scan that shows he sustained a high-grade hamstring tear, leaving him out of action for up to 10 weeks, with Ireland's final Six Nations match coming against England on March 18 - nine weeks from now.

Ireland are now struggling to find cover for Rory Best, with James Treacy and Niall Scannell in contention.