Last month, Japan rounded off a dominant Asian Cup campaign by defeating tournament hosts Australia 1-0 in the final to win the continental title for the third time in the last four editions.
The team also booked their spot at the 2027 Women's World Cup in Brazil after reaching the semi-finals of the Asian Cup.
But apparently, it was not enough to satisfy the expectations of the Japanese FA, as they decided to call an end to Nielsen's reign as the first foreign coach of the Japan women's team.
The Japan Football Association said Thursday that his contract had expired and they had not offered him a new one.
Women's national team director Norio Sasaki argued that Japan could not win next year's World Cup if Nielsen remained in charge, describing his coaching as "a little too lax, a little too soft."
"A more rigorous approach and harder training is needed. When I talked to him about what he could do to lift the team to the next level, it was as if he lacked passion", said Norio Sasaki.
Nilsen led Japan to 12 wins, four draws, and four defeats since taking over in December 2024.