Leinster and Ireland out-half Johnny Sexton looks set to miss this weekend's Heineken Champions Cup clash with Ulster.
Ross Byrne, who was named to start last weekend against Edinburgh but then replaced by Ciaran Frawley at late notice, is likely to replace Sexton for the Aviva Stadium tie.
Johnny Sexton recently returned to action after suffering from a thigh issue during Ireland' Six Nations game against Scotland. This came after he missed games in January with a knee tendon injury.
Per the Irish Independent, it is just one of many selection headaches facing boss Leo Cullen, with James Lowe also reported to be set to miss out due to the 'overseas' players limit. Scott Fardy starting in the second row and Jamison Gibson-Park's inclusion on the bench would ensure Lowe cannot play.
Leinster are already without Josh van der Flier, Devin Toner and Robbie Henshaw for the match.
Ulster's main absentee is Will Addison due to a back issue, with Craig Gilroy also on the injured list.
Saturday's quarter-final kicks off at 5.45pm and is live on Eir Sport.