Sean O'Brien doubt for Six Nations return

Leinster and Ireland flanker Sean O'Brien is unlikely to play a part in Ireland's quest for a Grand Slam in this year's NatWest Six Nations.

'The Tullow Tank' hasn't played since suffering a hip injury in the Champions Cup pool victory over Exeter Chiefs in December.

Leinster have confirmed that the 31-year-old will not be in the squad to face Scarlets on Saturday after Joe Schmidt had revealed that O'Brien was "on the cusp" of a return to Pro 14 action.

O'Brien underwent a small procedure in January after seeing a specialist to address some discomfort in his hip and is almost certain to miss the Scotland clash next Saturday.

“Sean O’Brien has returned to running and will look to step up his rehabilitation further this week from a hip injury,” said a Leinster statement.

"Seánie did a volume of running last week which is good and we're pleased with his progression," backs coach Girvan Dempsey told RTÉ News.