Leinster flanker Rhys Ruddock looks set for a significant spell on the sidelines following a hamstring injury sustained against Exeter Chiefs.
The 27-year-old limped off against the English outfit in their Champions Cup encounter on Sunday and has suffered a grade three tear, according to the Irish Independent.
It is a blow for both the province and Ireland, with Ruddock almost certain to miss the Six Nations and potentially the rest of the season.
Josh van der Flier, who came on to replace him in the back-row, is likely to start the return leg this weekend, while Dan Leavy and Jordi Murphy also come into contention.