Veteran lock forward Brodie Retallick shrugged off disruption to the start of the All Blacks' northern hemisphere tour as Leicester Fainga'anuku on Monday became the seventh player to leave the squad.
The three Barrett brothers, Scott, Jordie and Beauden, were among six New Zealand players who did not board the plane to Japan on Saturday after their grandmother died.
Sam Whitelock, Will Jordan and Folau Fakatava were also left at home because of injury, and back Fainga'anuku returned to New Zealand on Monday for family reasons.
The All Blacks called up four players as cover on Saturday and assistant coach Scott McLeod said selectors were weighing up a replacement for Fainga'anuku.
Retallick said the team had "probably lost more players in the space of 24 hours than you do in a series of test matches".
"That's life, and the boys that have come in for them are now on the ground and here, and we had our first training session today," said Retallick, who will win his 99th cap if he plays against Japan in Tokyo in the All Blacks' tour opener on Saturday.
"Although there is a lot of experience with the people not here, the boys that are here are just as eager and ready for an opportunity."
The All Blacks will travel on to Europe after the Japan clash to face Wales, Scotland and England on successive Saturdays.
McLeod said the Barrett brothers were expected to rejoin the squad on Thursday but it would be "too late for selection" against Japan.
Lock Whitelock and winger Jordan have both developed inner ear conditions and it is unclear when they will be fit to play.
Scrum-half Fakatava was ruled out of the tour with knee damage suffered in training last week.
The All Blacks have not played since thrashing Australia 40-14 a month ago to win the Rugby Championship.
Japan have played three matches against Australia A in recent weeks and Retallick said the All Blacks would have to be careful against a side who have "knocked off some big teams".
"There's a real edge around camp that we're obviously refreshed from having a break but we're also very conscious that we need to carry on where we finished the Rugby Championship against Australia here in Japan, and then as we move on to Europe," he said.
The All Blacks are looking to continue their momentum after a strong finish to the Rugby Championship.
The celebrations after winning the title were a huge contrast to the start of the competition when New Zealand were beaten 26-10 in South Africa, after losing a home series to Ireland, their fifth defeat in six tests.
Retallick said the team's poor run of form was "a real wake-up call".
"We fully understand that coming to Japan this week before we go off to Europe is going to be another massive challenge, because we did lose a few games up there at the end of last year," he said.
"Now we feel we're heading in the right direction, we just need to carry on and keep doing it week in, week out."