Japan's football association on Wednesday condemned the "shameful behaviour" of fans who racially abused Zion Suzuki online following the goalkeeper's performances at the Asian Cup.
Pre-tournament favourites Japan were beaten 2-1 by Iraq in the group phase on Friday in Doha with Suzuki responsible for one of the goals.
The US-born 21-year-old, whose father is Ghanaian-American and whose mother is Japanese, said he was subsequently racially abused on social media.
There were also two high-profile instances of racist abuse directed at players in Italy and England during matches at the weekend.
"We have a zero-tolerance stance and our aim is to stamp it out," Japanese Football Association president Kozo Tashima said in a statement.
He added: "We are aiming to win the Asian Cup currently being held in Qatar and the players, manager, staff and JFA are all united."
"(But) posting cruel racist and other abuse online is an invasion of human rights and privacy," he said.
"It goes against the values of a society that respects diversity and is shameful behaviour."