Ireland scrum-half Conor Murray says he's looking forward to playing alongside 'laid-back' Jack Carty in Saturday's crunch Pool A clash with Rugby World Cup hosts Japan.

Connacht fly-half Carty only made his international debut in Italy in February, and now the 27-year-old will make his second Test start against the Brave Blossoms.

Ireland had the more experienced Joey Carbery available for selection but head coach Joe Schmidt opted to start Carty instead, following his impressive showing off the bench in the win over Scotland in Yokohama.

Johnny Sexton is being protected after a picking up a bang to the thigh in last weekend's win, but Ireland remain unfazed by the absence of 2018's World Player of the Year.

British and Irish Lions scrum-half Murray admitted he relishes linking up with Carty, a playmaker he believes is able to keep his head amid Test arena intensity.

"He's quite a calm character, Jack, which is good to have outside you," said Murray.

"Like anyone that comes into the set-up there's a pressure to learn and step up on you and he's responded really well to that.

"He's got to grips with the way we play, the tactics and phase-calls and what's expected of him.

"That laid-back nature has aided him in coming into an environment like this and learning off the likes of Johnny and Joey, who is actually younger than him but has been around the set-up for a while.

"So, yeah, I'm excited to play with Jack. He takes it in his stride, he's played really well any time he's been given the chance whether in the Six Nations or the summer series, coming over here and coming on last weekend he did really well. I'm excited."

Tadhg Furlong touches down against Scotland

Meanwhile, Murray says Joe Schmidt's squad have settled into life in Japan well and are ready for Saturday's showdown with the host nation.

The two unbeaten teams go head-to-head with the winner likely to top the pool and, in all probability, avoid champions New Zealand in the quarter-finals.

Ireland opened their account with a comprehensive win over Scotland last Sunday and they are getting used to the muggy conditions.

"It’s always a lot easier after a win and when you perform," said Murray, speaking to RTÉ Sport.

"The weeks go quicker and we’ve settled in pretty well. The biggest thing was getting a win and getting a performance and that makes settling in to life in Japan a lot easier.

"The first game is out of the way now and we’d hope to get better and build on that performance. It has been a great week here in the middle of nowhere, a great week to recharge and recover, get away from it all and get ready for a massive occasion.

"These opportunities don’t come around to often – playing the host nation at a World Cup. I know there’ll be more Irish fans coming out this week and the Japanese fans will create a great atmosphere.

"In terms of the game, they’re not to be taken lightly. The guys who toured here two years ago, the experience they had was really, really tough. They like to play at a rapid pace and if you let them they have dangerous players so it’s a big game for us."

Ireland won a two-game series in Japan in 2017 with players like Jacob Stockdale, Andrew Conway, Joey Carbery, Jack Conan, Josh van der Flier and Andrew Porter all in the touring party.

Ireland out-half Jack Carty

Ireland's win over Scotland was a game of two halves in terms of weather – warm and muggy in the first half, heavy rain after the break.

Said Murray: "That first half against Scotland when the rain stayed away and the humidity was there; the ball gets a bit greasy and it’s tough on the lungs.

"That’s what the summer was for, the training we had in pre-season that we went through and the warm-weather camps we did, you could feel that effects of that and we were reaping the benefits.

"The second half it can be completely different, as you saw with the rain and thankfully we had a good lead so Scotland had to force it a little bit which played into our hands in terms of getting off the line and putting them under pressure.

"I don’t think it’s going to be like that this weekend, I think it’s due to be a bit drier and humid like it was in the first half so that could play into Japan’s hands and the pace they like to play at.

"But I think we’re getting used to this weather, we’re enjoying it and hopefully we can put a bit of a performance together ourselves."

Follow Ireland v Japan on Saturday (kick-off 8.15am) via the live blog on RTÉ.ie/Sport andthe NewsNowApp, watch live on RTÉ2 from 7.30am or listen to live match commentary on RTÉ Radio 1.

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