Eddie Jones vowed Japan will have "a red-hot go" against his former team England when the two sides meet in Tokyo on Saturday.
Jones named four uncapped players including a university student in an inexperienced line-up for his first match in charge of his second spell with Japan.
The feisty Australian coach said he wants to "change Japanese rugby", starting this weekend at the National Stadium in Tokyo, where temperatures are set to reach 30 degrees Celsius (86F).
He will meet his former assistant Steve Borthwick, now England head coach.
"Of course England have got experience, they're three years into a cycle under Steve Borthwick, we're 10 days into a cycle," Jones told reporters on Thursday.
"So there's a gap there but we've got no excuse, we've prepared really well and we're going to give it a red-hot go on Saturday."
Loose forward Michael Leitch, who played under Jones during the Australian's first stint as Japan head coach from 2012 to 2015, was named captain.
Jones retained only three starting players from the 39-27 loss to Argentina at last year's World Cup that confirmed their first-round exit.
The new faces include 20-year-old university full-back Yoshitaka Yazaki, who Jones said had "a fantastic future".
"We brought him into camp and every time he's trained he's got better and better," said Jones.
"Yes he's young, he lives with 150 other students in a dormitary.
"He's not a great student at the moment, but he's a great student of rugby."
Jones led England to the 2019 World Cup final, where they were beaten by South Africa.
He was fired as England boss at the end of 2022 and was replaced by Borthwick, who took the team to the semi-finals of last year's World Cup.
Jones said Borthwick was "doing a great job".
"England's a high-pressure job, you get more scrutiny than probably any other job in the world," he said.
"I think he's handled that pretty well."
Japan (15-1)
Yoshitaka Yazaki; Jone Naikabula, Dylan Riley, Tomoki Osada, Koga Nezuka; Seungsin Lee, Naoto Saito; Faulua Makisi, Tiennan Costley, Michael Leitch; Warner Dearns, Sanaila Waqa; Shuhei Takeuchi, Mamoru Harada, Takayoshi Mohara
Replacements: Atsushi Sakate, Shogo Miura, Keijiro Tamefusa, Amanaki Saumaki, Kai Yamamoto, Shinobu Fujiwara, Rikiya Matsuda, Samisoni Tua
