Leinster and Ireland outhalf Johnny Sexton has passed all of his Head Injury Assessment tests after taking a late hit from Francois Steyne in their European Cup tie against Montpellier. Steyne paid the price with a red card.
But hooker Sean Cronin is out with a hamstring injury and will not be available to Leinster for approximately 10 weeks, a lengthy spell that also takes him out for most of the Six Nations Championship.
As Leinster face into their final away Pool match against French side Castres and determined to earn a home quarterfinal, Cronin will be viewing only, although Isa Nacewa, Robbie Henshaw and Sean O'Brien will all undergo further assessments later in the week.
Nacewa was withdrawn early in the second half at the weekend with a dead leg, while centre Henshaw was taken out as a precautionary measure after he felt tightness in his thigh.
Similarly flanker O’Brien felt tightness in his calf last week and Leinster decided not to take the risk of playing him against the French team.
The good news for Leo Cullen is that his fullback Rob Kearney came through the Montpellier match with no issues after his return from an ankle injury and is available for selection this week.
Leinster play Castres on Friday in Stade Pierre Antoine.
