Former Australia midfielder Leah Blayney followed Women's Asian Cup-winning coach Nils Nielsen out the Japan exit door on Monday, leaving as assistant coach at the end of her contract.
Japan dumped Nielsen at the end of his contract last week, just 12 days after he led them to their third Asian title in four tournaments.
Japanese football chiefs accused the Dane of being a "lax" coach, and said they did not believe he could win next year's World Cup in Brazil.
Former Matildas player Blayney has also been let go and will not take part in Japan's three away friendlies against the United States this month.
"Japan assistant coach Leah Blayney has left upon the completion of her contract," the Japan Football Association said in a statement.
Blayney won 16 caps for the Matildas and also coached Australia's Under-20 team.
The 39-year-old had been with Japan since last year.
Former assistant Michihisa Kano has been named as Japan's interim coach for the friendlies against the US.