Cronin, 32, appears to have paid the price for a poor performance as starting hooker in Rome 10 days ago, a game missed by both fly-half Carbery and centre Henshaw due to injury.

Yet while Carbery was named in head coach Joe Schmidt’s 37-man squad on Wednesday, both Cronin and Henshaw were absent and all three will be unavailable on Sunday.

There were four fly-halves in the group training at Carton House with Ross Byrne added to the squad earlier in the day to join first-choice Johnny Sexton, Carbery and Jack Carty, who made his debut off the bench in the bonus-point victory against Italy.

Assistant coach Simon Easterby said Sexton was fit to face the French despite taking a limited part in training last week but that the fourth-round fixture was perhaps too early for Carbery to pass fit.

“Joey trained today and ran and conditioned pretty well. It might be just a little bit too soon for him. Not being a medic, I'd say he's unlikely to feature this week. He's probably recovered quicker than we expected but if he is 50/50, you wouldn't play a player.

“We have to make sure we're in a better position than that.”

As for Cronin, replaced in the squad by Ulster’s Rob Herring, who joins up with fellow hookers Niall Scannell and team captain Rory Best, forwards coach Easterby insisted the Leinster front-rower still had a future with Ireland beyond the 68th cap he collected last time out and that this was an opportunity to assess less experienced players.

“I guess we're looking continually to build some depth in positions. Sean has been involved in the first three games, he has started in Italy, and in a specialist position like hooker, probably only nine and maybe 10 as well where you don't get guys playing other positions,” Easterby said.

“We're just looking to continually build some depth and find out a bit more about players that we need to work with towards what's coming up in the next couple of weeks and the end of the year.

As for hurting Cronin’s World Cup hopes, Easterby said: “Certainly not, no.”

The forwards coach was non-committal about whether Henshaw (dead leg) and Dan Leavy (calf) could be fit in time to face Wales in Cardiff in the final round on March 16.

“Possibly. Again it's about making sure they're right and ready to play and not compromising their return. It may well be that they don't feature but we will assess that as we go along this week and then with the short turnaround the week after, it would be great if we could have some fresh bodies coming back in, but it might be too soon for both of them.”