Joey Carbery’s participation in the World Cup appears to be in a degree of jeopardy, with the IRFU set to confirm on Wednesday that the ankle ligament damage which the Munster outhalf suffered against Italy last Saturday will sideline him for an estimated six weeks.

Applied strictly, that timeframe would rule the 23-year-old out of the remaining warm-up games against England at Twickenham on Saturday week and Wales, both away and at home, as well as Ireland’s pivotal pool opener against Sootland in Yokohama on Sunday, September 22nd.

If he were to recover fully after exactly six weeks, Carbery would then conceivably be fit for Ireland’s second pool game against the hosts, Japan, six days later. Of course, it could be that Carbery will prove his fitness in time for the Scottish game, and his classy, inventive and varied display for almost 50 minutes in his first game for three months last Saturday showed he can quickly hit form after a lay-off.

But while Joe Schmidt will be extremely keen to have Carbery in Ireland’s 31-man squad, this prognosis is cutting it fine, and the head coach would also like 31 fully fit players.

True, as Carbery’s performance against Italy (when the head coach gave him freedom to play what was in front of him) also showed, he has a defence-opening array of tricks which few others possess.

However, a possible absence of six weeks would not only be very disappointing and frustrating for player and management alike, it would also be less than ideal for Ireland’s World Cup preparations.

Recurring hamstring problems restricted Carbery to two appearances off the bench for Ireland in the Six Nations and just two subsequent starts for Munster, leaving him with just three games since February going into the World Cup, and just 113 minutes on the pitch for Ireland in the calendar year.

At the very least, this latest setback will seemingly prevent Carbery from gaining more valuable time on the training ground and in matches, and would leave him less than primed come Japan.

It may also increase the load on Johnny Sexton, fit again after suffering a thumb injury in camp, but either way it will assuredly prompt Schmidt and his assistants to revise their selection strategy for the remaining warm-up games and conceivably the make-up of the 31-man squad as well.

Four years ago, the Irish management opted for five half-backs, with second-choice outhalf Ian Madigan also providing cover for the two scrumhalves, Conor Murray and Eoin Reddan.

If, say, Schmidt and co had been inclined to opt for three scrum-halves as well as Sexton and Carbery, with John Cooney providing cover at ‘10’, they may well be inclined to revise such thinking now.

Certainly the case for granting Jack Carty and Ross Byrne more game time in the remaining warm-up games, with a view to at least one of them travelling to Japan, has been strengthened.

At the very least, Carbery’s World Cup hopes appear to be delicately balanced and Ireland’s World Cup ambitions seem at least slightly unhinged.