NZ's CJ Bott. Photo: PHOTOSPORT
The Football Ferns will face their highest-ranked opposition in 18 months - without their head coach.
Jitka Klimkova will be absent for two matches against world number seven Japan due to what New Zealand Football has described as an employment matter.
Assistant coach Michael Mayne will step up to guide the world number 28 side for the matches to be played in Spain. He will be assisted by former Wellington Phoenix women's coach Natalie Lawrence after the Football Ferns' other regular assistant Keri Sarver is also missing.
Mayne said he did not know how long he would be in the interim head coach role but the team were not disregarding the situation they found themselves in.
"I want to keep this as consistent as possible but also I have to make tweaks given the circumstances that are going to allow me to prepare this team, so it was not ignoring what was going on but there is two key priorities for me making sure that we look after each other in here and we stay together and we stay united and then focus on the football.
"These are professional players that are playing a world-class team in a few days they have, as this group does, rallied around each other they're supporting me really well ... the situation is one where I don't think we can avoid what is going on but I think the players are handling themselves extremely well given the circumstances."
Saturday morning's game will be the first time Mayne will be head coach of the side and after a disrupted build-up he will be charged with finding a plan to counter a Japan side that includes many players that took their team to the quarter-finals of the 2023 FIFA Women's World Cup.
Japan will call on players from Italian club AS Roma, Germany's Eintracht Frankfurt, Netherlands' Feyenoord and England's West Ham United, Manchester City, Liverpool, Manchester United and Chelsea.
Whereas Mayne has been dealt a blow with midfielder Macey Fraser withdrawing from the squad on Thursday for personal reasons to return to her NWSL club Utah Royals.
Macey Fraser has left the Football Ferns camp to return to the Utah Royals. Photo: John Davidson/Photosport
Mayne hoped to have Fraser back in the Football Ferns in the future.
The Football Ferns are on a seven-match unbeaten run and beyond the Japan friendlies are looking to the Olympics.
New Zealand qualify for the Paris Olympics with a 11 - 1 win over Solomon Islands. Women's Olympic Football Tournament, Samoa, 2024. Photo: PHOTOSPORT
"The position we're in there's no time to make any big changes to the plan and for me that's the big driver. Olympics is what we're preparing for and we've got to select this team shortly after this tour.
"I need to get clarity on where the team is at and there is no better opposition right now than Japan to prepare for that."
Mayne wanted players for the Olympics who could cope with change.
"It's a smaller squad you can name for the Olympics so we have to be clear on the diversity of the squad and who can take on information quickly and apply it.
"It might be that they have to be quite adaptable so I am working through that for game one [against Japan] around what our squad looks like.
"But what I want to come out with is being prepared and having some clarity for those discussions around the different roles and where our players are at because we've got a short turnaround after this before we go into the Olympics."