Paul O’Connell has no reservations about the possibility of Ross Byrne, Jack Crowley or Ciaran Frawley starting a World Cup match in place of influential Ireland captain Johnny Sexton.

Suspension has ruled fly-half Sexton out of his country’s warm-up matches against Italy, England and Samoa, leaving a trio of inexperienced understudies vying to stake their claim for the role.

Frawley remains uncapped at international level, while his Leinster team-mate Byrne and Munster man Crowley have just four Test starts between them.

Veteran Sexton will complete his three-match ban in time to feature in Ireland’s World Cup opener against Romania on September 9 but he is short of match fitness having not played since March due to injury.

Although forwards coach O’Connell acknowledges the stand-in options are Test rookies, he would back each of them to perform on the biggest stage if required.

“I’d be confident in all of them,” he said, ahead of Saturday’s Dublin clash with Italy.

“One of the strengths we have is that we’ve good clarity on how we’re trying to play the game and the players have to take ownership of that clarity quite a lot.

“You do figure out a guy that’s unsure very, very quickly. But all of our guys know how we want to play.

“They don’t have as much practice at it or as much experience as Johnny has of taking ownership of it but that’s why these few weeks will be great for them.

“We play differently to Munster and to Leinster and the guys that are there but there is a lot of similarities as well so it’s nothing massively new to them.

“They’ve all driven the ship for their provinces in big, big games and done really well. There’s a little bit of a tweak to how we do things and they’ve got to pick that up.”

Sexton’s last competitive action was four and a half months ago when he limped off with a groin issue during Ireland’s Grand Slam-clinching win over England.

The 38-year-old, who has 113 caps for his country, has been training fully with Andy Farrell’s 42-man preliminary squad this summer ahead of his last competition before retirement.

Ireland’s selection is due to be cut to a final 33 on August 28 and O’Connell has urged those who do miss out to not feel too disheartened.

“It’s not all or nothing,” said the 43-year-old, who represented Ireland at four World Cups between 2003 and 2015.

“You hope that by being in here, training with us, training with good players, that players are improving and they’re looking at their opportunity to get a chance, to try to get picked for the World Cup and, if they don’t, that they break in in the future.

“They all want to go to the World Cup for sure, but selection for the World Cup is not an all-or-nothing thing.

“I’m sure plenty of guys are going to be disappointed.

“They’ve their sights set on getting their chances and taking it but I think they’re all going to be better on the back of this pre-season.”