Asia champions Japan need 'different tools' to win World Cup - coach
Japan beat Women's Asian Cup hosts Australia 1-0 in Saturday's final in Sydney to lift the trophy for the third time in four tournaments.
Nielsen's side dazzled along the way, scoring 29 goals and conceding just one to lay down a marker ahead of next year's World Cup in Brazil.
Japan are the only Asian team to have won the world title and Nielsen said they would need to keep improving if they want to do it again.
"We found some parts of ourselves that are really strong," the Greenland-born coach said after returning to Tokyo.