Japan has made six changes, two of them positional, to the starting side that beat Russia for the Pool A match against Ireland on Saturday in Shizuoka.
Captain and flanker Michael Leitch, prop Asaeli Ai Valu, lock Wimpie van der Walt, and wing Lomano Lava Lemeki have all dropped into the reserves.
Regular No 8 Amanaki Lelei Mafi was back after recovering from a shoulder injury against South Africa in the last World Cup warmup this month. Prop Jiwon Koo, lock Luke Thompson — the oldest player in this World Cup at 38 — and fullback Ryohei Yamanaka come up from the reserves.
William Tupou has switched from fullback to wing for the first time in his test career, in place of Lemeki, and Kazuki Himeno has switched from No 8 to flanker in place of Leitch.
Openside flanker Pieter Labuschagne becomes the third foreign-born player to captain Japan in a World Cup match.
For Ireland, Jack Carty will start at flyhalf.
Jonathan Sexton injured a quad against Scotland last Sunday and wasn't to be risked.
Carty made his Ireland debut in February and will start for only the second time.
Ireland made four changes — all in the backline — to the starting XV that beat Scotland 27-3. The forwards are unchanged after dominating Scotland.
Wing Keith Earls and fullback Rob Kearney have recovered from injuries, and Chris Farrell is at inside center for Bundee Aki, who was also hurt against the Scots but was available.
Joey Carbery has also recovered from an ankle injury against Italy in July to make the reserves.
16. Atsushi Sakate, 17. Isileli Nakajima, 18. Asaeli Ai Valu, 19. Wimpie van der Walt, 20. Michael Leitch, 21. Fumiaki Tanaka, 22. Rikiya Matsuda, 23. Lomano Lava Lemeki
Ireland
15. Rob Kearney, 14. Keith Earls, 13. Garry Ringrose, 12. Chris Farrell, 11. Jacob Stockdale, 10. Jack Carty, 9. Conor Murray, 8. CJ Stander, 7. Josh Van der Flier, 6. Peter O'Mahony, 5. James Ryan, 4. Iain Henderson, 3. Tadhg Furlong, 2. Rory Best (c), 1. Cian Healy.
Reserves:
16. Sean Cronin, 17. David Kilcoyne, 18. Andrew Porter, 19. Tadgh Beirne, 20. Rhys Ruddock, 21. Luke McGrath, 22. Joey Carbery, 23. Jordan Larmour
How to watch:
The Herald will have live updates of the match from 7.00pm. Spark Sport coverage starts at 6:45pm. Kickoff is at 7:15pm.
Played: Ireland and Japan have played each other seven times with Ireland winning every match. Their biggest winning margin came in the year 2000, winning 78-9.
Last match: Ireland won 35-13 in Tokyo, 2017.
Prediction: Ireland by 20.
Group standings
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