Tadhg Furlong has emerged as an injury worry for head coach Andy Farrell, ahead of Ireland's Six Nations resumption next month.
The Leinster prop didn't feature in his province's final Pro 14 and Heineken Champions Cup games, after struggling with a back injury.
Leinster have confirmed today that Furlong has now picked up a calf injury which will sideline him for "a number of weeks".
The province's latest medical update says: "Tadhg had successfully returned from his back injury but picked up a minor calf injury during preparations for the Saracens game and will be unavailable for a number of weeks as a result."
Ireland's Six Nations campaign resumes against Italy on the 24th of October, before they take on France in Paris a week later.
Should Furlong be passed for those games, he could potentially be returning to test rugby having not played a game at any level for seven months.
In better news for Leinster, Robbie Henshaw is available for selection for their opening Guinness PRO14 game of the new season, having completed the Graduated Return to Play Protocols for a head injury suffered in their Heineken Champions Cup quarter-final defeat to Sarens nine days ago.
The province also say Dan Leavy will be unavailable for selection this weekend. The flanker's training load is continuing to increase though, as he steps up his recovery from a serious knee injury against Ulster 18 months ago.
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