Ireland will aim to build on their impressive opening World Cup win over Scotland when they face unbeaten hosts Japan in Shizuoka on Saturday.

Coach Joe Schmidt has opted not to risk fly-half Johnny Sexton because of a thigh strain so Jack Carty is handed only a second Test match start.

Backs Rob Kearney, Keith Earls and Chris Farrell also replace Jordan Larmour, Andrew Conway and Bundee Aki.

A surprise Japan change sees skipper Michael Leitch left on the bench.

Instead, head coach Jamie Joseph opts to bring fit-again Amanaki Mafi into the back row, with flanker Pieter Labuschagne leading the Brave Blossoms for the first time.

Japan beat Russia in tournament curtain-raiser

Japan defeated Russia 30-10 in last Friday's tournament opener helped by Kotaro Matsushima's hat-trick of tries.

Mafi's inclusion for Leitch, which sees Kazuki Himeno move from the back of the scrum to blind-side flanker, is one of three personnel changes in the pack.

Koo Jiwon comes into the front row for Asaeli Ai Valu as Luke Thompson replaces Wimpie van der Walt at lock.

Wing Lomano Lemeki also makes way as Rhoyei Yamanaka comes in at full-back with Will Tupuo moving to the left wing.

Japan broke into the world's top 10 under Joseph's predecessor Eddie Jones, and have become almost a permanent fixture there under former All Black Joseph.

But they no longer carry the element of surprise following their heroics at the last World Cup four years ago, when they produced the biggest upset in the tournament's history by stunning South Africa 34-32.

Hosts claim Healy scrummages illegally

After regrouping from a worrying pre-tournament build-up to hammer the Scots in Yokohama, Ireland will be expected to have too much power for the hosts.

The build-up to the match has included Japanese claims of Irish scrummage illegality from host country prop Yusuke Kizu and coach Joseph.

Kizu said that Cian Healy "steps out" and illegally angles in at scrum-time, although Joe Schmidt dismissed the claim.

"Yes, at times they are illegal, but at all times they are a very strong scrum," said Joseph.

"But we've really improved our scrum and line-out recently. And it's an area we've been focusing on all week."

The teams

Japan: Yamanaka; Matsushima, Lafaele, Nakamura, Tupou; Tamura, Nagare; Inagaki, Horie, Koo, Thompson, Moore, Himeno, Labuschagne (capt), Mafi.

Replacements: Sakate, Nakajima, Valu, Van Der Walt, Leitch, Tanaka, Matsuda, Lemeki.

Ireland: Kearney; Earls, Ringrose, Farrell, Stockdale; Carty, Murray; Healy, Best, Furlong, Henderson, J Ryan; O'Mahony, van der Flier, Stander.

Replacements: Cronin, Kilcoyne, Porter, Beirne, Ruddock, McGrath, Carbery, Larmour.

What they said

Ireland head coach Joe Schmidt: "We always knew we were going to have to manage this start to the tournament because of a six and a five-day turnaround.

"We do know that the challenge this weekend is going to be particularly tough."

Japan head coach Jamie Joseph: "Our goal is that we want to do something that's never been done in Japan before and that's top eight. That's what we're about.

"We're focusing on us and making sure they are prepared physically, mentally and tactically to play the best game of their lives."

Match stats

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