Major doubt.

Leinster are once again sweating on the fitness of scrumhalf Luke McGrath ahead of the crucial Champions Cup semi final clash with Scarlets in a fortnight.

The Ireland international was forced off in Leinster’s quarter-final win over Saracens last Sunday, having only recently returned from a long-term problem that kept him out almost the entire Six Nations.

Head coach Leo Cullen revealed today that McGrath is currently in a protective boot and has been unable to train on the field this week.

“He’s not too bad,” Cullen said this afternoon.

“We’ll see how he goes next week, whether he starts running or not. He’s walking around in a boot at the moment, he hasn’t trained on the field this week.”

Should McGrath miss out, Leinster will not only be without their first-choice scrumhalf for the Scarlets game, but also face the prospect of losing either Scott Fardy or James Lowe – who both started in the win over Saracens.

Leinster can only have two players in their squad from Australia or New Zealand under Champions Cup regulations, meaning Fardy or Lowe would have to drop out to make room for McGrath’s likely replacement Jamison Gibson-Park.