Sean O'Brien's comeback from a hip injury lasted just over a quarter of Leinster's Pro14 10-10 draw at the Scarlets at a rain-drenched Parc y Scarlets.
The flanker, who would have hoped to be involved in Ireland's Six Nations game with England next Saturday, was replaced by Max Deegan after 27 minutes after sustaining what appeared to be an arm/shoulder injury.
The back rower, who underwent surgery to try and fix the unspecified hip issue, last played for the province in their Champions Cup win over Exeter in December.
A frustrated looking Sean O'Brien is off the field after just 27 minutes for Leinster. Not good. Looked like arm/shoulder issue.
— Ciarán Ó Raghallaigh (@Ciaran_O) March 9, 2018
Ireland boss Joe Schmidt had spoken about his hopes that the experienced forward could play some part in their Six Nations campaign but that now looks unlikely.
Meanwhile, fly-half Dan Jones kicked a last-gasp penalty to secure Scarlets a dramatic 10-10 draw
Scarlets were trailing 10-7 and just as the clock went red referee Nigel Owens awarded the home side the key penalty.
From 28 metres Jones put the kick through the posts.
The draw keeps Scarlets three points behind Leinster in Conference B.
