Japan heads into its first test with Ireland showing five changes and one positional switch from the team that started last week's 33-21 win over Romania.
Head coach Jamie Joseph named his 23-man squad Thursday for Saturday's game at Shizuoka's Ecopa Stadium following a week in which Harumichi Tatekawa, Akihito Yamada, Yu Chinen and 98-cap veteran Hitoshi Ono all pulled out of the squad with injury.
In the backs, William Tupou wins his first cap and links up with Coca-Cola Red Sparks teammate Timothy Lafaele (who moves from 13 to 12) in the centers. Yu Tamura gets the nod at flyhalf, while Kotaro Matsushima is named on the wing in place of Yamada.
There are two changes to the Brave Blossoms' pack, with Keita Inagaki and Heiichiro Ito — who both started last week's game on the bench — packing down either side of captain Shota Horie in the front row.