Joey Carbery has never started a Six Nations match for Ireland. He is likely to be named tomorrow to start his first tournament game for Ireland, against hosts Japan on Saturday morning.

The out-half made his international debut at the age of just 20 against the country of his birth when Ireland beat New Zealand in Chicago in 2016.

Since then he has amassed 19 caps but made only six starts, none of which came in the Six Nations, almost a jarring stat when one considers the amount of time that Joe Schmidt has had to bed him in.

Back in early 2018 there was a lot of discussion about starting Carbery in one of the home fixtures of the Six Nations campaign, when Italy, Wales and Scotland were the visitors.

However, Schmidt opted not to hand the 10 jersey to the understudy when he had a fully fit Johnny Sexton on hand and the veteran started all five games in the Grand Slam run.

The opening Test of the tour to Australia in 2018, an 19-9 loss, remains his only big-game start. The others have come against the USA (2), Italy (2) and Fiji.

And while the Lions fly-half remains available for selection for Saturday's game against Japan, given that he twice received on-field treatment and was not fit enough to goal-kick after the second try against Scotland on Sunday, it now looks likely that Carbery will be named at 4am on Thursday when Schmidt reads over the team-sheet. 

POSSIBLE IRELAND TEAM TO PLAY JAPAN 

It is well known that the 23-year-old plays a different game to Sexton, the younger man posing a more immediate threat at the gainline and from broken play.

Sexton's days of beating defenders one-on-one look over and the famous loop moves in the back field are less in evidence these days.

All that makes Ireland slightly less predictable when Carbery is on the field.

Against Fiji (below) in 2017, in his second start, Carbery broke his arm after an hour but Schmidt was impressed by what he saw.

A composite of the boss’s post-match praise:  "a bit special...ability to organise others is coming along...vision is really good...the threat he poses at the line himself, he ducked and dived...brave...team-oriented."

And speaking to RTÉ Sport while recovering from that injury, Carbery was asked about his smooth transition from full-back at Leinster to Ireland out-half: "You always think the step up to international rugby is going to be really tough.

"But to come into a training environment in Carton House with Joe and it's almost like match-intensity so you do have to pick [the pace] up quite quickly."

While he only last 49 minutes against Italy in August before suffering what looked like a serious ankle injury, the Athy man made Ireland’s backline tick and keeping an opposition defence guessing is half the work.

The fact that Schmidt took him to Japan while carrying an injury – similar to keeping Robbie Henshaw on board – also tells a story of how important his presence is to the boss.

Frustrated at finding limited opportunities at Leinster, behind both Sexton and Ross Byrne, Carbery made the move south to Munster in 2018. It was a move that pleased Schmidt as he worked to build squad depth for Japan.

He made an immediate impact, scoring three tries in his first eight games for the province.

And he also impressed in the pool stages of the Heineken Champions Cup, playing five of the pool games, from which he was man of the match in two.

Those being the home and away games against Gloucester when he scored 42 points, including three tries (above).

But another big-game opportunity was missed when he got injured in the quarter-final win over Edinburgh. Munster could have done with their out-half as they got overrun by Saracens in the semi-final.

As mentioned above opportunities at Leinster were limited and while he played the full 80 minutes of the 2017 semi-final loss to Clermont, that was at full-back.

Again, the following season he started in just two of the European pool games, neither one at out-half.

There is nothing to suggest that Carbery doesn’t have a big game temperament, he has slotted in seamlessly when called upon.

"He is a cool customer," said Rory Best after Carbery replaced Sexton 23 minutes into Ireland’s win over Scotland in this season’s Six Nations, "I think he's benefiting greatly from being down in Munster."

"He's doing really well there and you can just see him growing into the game.

"Some of the things that you see him doing...when that ball was scrappy, he went down and picked it up and made something out of nothing and that's what Joey can do and I thought he bossed the forwards well in a game that was very difficult.

"I thought Joey did super. That's ultimately what we need."

Ireland also need to beat Japan in a convincing manner. The team has some of its 2018 swagger back but current confidence levels should not be taken for granted. 

The fact remains that Carbery is largely unproven in the high-pressure competitive international games.

Providing he gets the nod for Saturday's game, that test is coming and he should pass with flying colours. 

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