Ireland captain Johnny Sexton came off injured after only 24 minutes of Leinster's 35-5 season opening win against Dragons in the Guinness PRO14.
The former world player of the year applied ice to his calf after he came off at the RDS and the issue will be a concern to Ireland head-coach Andy Farrell ahead of their Six Nations matches against Italy and France later this month.
Two other members of Farrell's squad, Andrew Porter and Max Deegan, also picked up knocks for the defending PRO14 champions.
Deegan was substituted after injuring his knee while Leo Cullen says prop Porter has a "lower limb issue" while Ciaran Frawley failed a HIA after a collision with Jamie Roberts.
We’ll see the extent of all three tomorrow," Leinster boss Cullen added of the three injured Ireland players in his post-match press conference.
“I think they’re OK. Max looked the one, it’s his knee I think. The other two didn’t seem to be too bad."
James Lowe ran in two tries and Jordan Larmour, Ryan Baird and Garry Ringrose also went over the whitewash as Leinster eased to a 30-point victory over their Welsh opponents.
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