Andrew Conway, Rory Scannell, Luke McGrath and Dan Leavy will make their first Ireland starts against Japan on Saturday.
Joe Schmidt has made six changes to the side which hammered United States in New Jersey last weekend.
Conway comes in for his maiden start, so Keith Earls moves to the left wing and Simon Zebo is included at full-back for the clash in Shizuoka.
Scannell will play alongside influential centre Garry Ringrose, while half-back McGrath also starts and Leavy gets the nod at openside flanker.
Rhys Ruddock has been named as captain for a second time and number eight Jack Conan has also been included by Schmidt.
Ireland team to play Japan: Simon Zebo, Andrew Conway, Garry Ringrose, Rory Scannell, Keith Earls, Paddy Jackson, Luke McGrath; Cian Healy, Niall Scannell, John Ryan, Quinn Roux, Devin Toner, Rhys Ruddock, Dan Leavy, Jack Conan.
Replacements: James Tracy, Dave Kilcoyne, Finlay Bealham, Kieran Treadwell, Jack O'Donoghue, Kieran Marmion, Rory O'Loughlin, Tiernan O'Halloran.