Méabh Deely, Natasja Behan, Aoife Dalton and Dannah O'Brien have all been handed debuts by Ireland head coach Greg McWilliams for Saturday's first Test against Japan in Shizuoka.
McWilliams has named a youthful squad for the first of their two tour matches, with second row Taryn Schultzer and centre Leah Tarpey also in line to make their debuts from the bench.
With a number of injuries and players unavailable, there are just nine survivors in the starting team from the final round of the Six Nations in Scotland, with Enya Breen and Aoife Doyle the only two backs who retain their places.
Connacht and Blackrock's Deely makes her Test debut at full-back having previously featured for the Ireland Sevens side, while wing Behan was part of the wider Ireland squad for their TikTok Women's Six Nations earlier this year.
O'Brien (above) comes in at out-half, having just completed her Leaving Cert. The Carlow teenager is a member of the Women's National Talent Squad, as is 19-year-old Dalton, who is joined by Breen in the centre.
The pack is quite settled from the Six Nations, with just one change from the most recent game against Scotland.
Nichola Fryday captains the side, and as usual partners Sam Monaghan in the second row, with Hannah O'Connor, Edel McMahon and Dorothy Wall completing a familiar back row.
Katie O'Dwyer is the only new change in the pack, propping down alongside hooker Neve Jones, with Linda Djougang starting at loosehead.
Ireland: Méabh Deely; Natasja Behan, Aoife Dalton, Enya Breen, Aoife Doyle; Dannah O'Brien, Ailsa Hughes; Linda Djougang, Neve Jones, Katie O'Dwyer; Nichola Fryday (capt0, Sam Monaghan; Dorothy Wall, Edel McMahon, Hannah O'Connor.
Replacements: Emma Hooban, Chloe Pearse, Christy Haney, Taryn Schultzer, Grace Moore, Nicole Cronin, Leah Tarpey, Molly Scuffil-McCabe
Follow Japan v Ireland (Saturday, 11am) via our live blog on rte.ie/sport and on the RTÉ News App.