Former footballer Son Woong-jung is a public figure in South Korea and authored a best-selling memoir detailing how he helped his son become one of the best strikers in the English Premier League.
But the family of a 12-year-old, identified only as Kim, told police he was the target of foul language just weeks after his enrolment at Son senior's academy in November.
"I was called out by coach Son for making a mistake during a passing practice," Kim alleged in the interview.
The coach then continued with a tirade of foul and abusive language and called the boy various offensive names on multiple different occasions, Kim told police investigating the academy.
The boy was also allegedly hit with a corner flag by Son Heung-yun, the brother of the Tottenham striker, leaving a large bruise on his left thigh.
Son Heung-yun previously said that he and Son Heung-min were "hit by our father a lot when training, which is unimaginable these days".
"Some of our neighbours even doubted he was our real father," he told AFP in a 2019 interview.
Son senior has described his actions at the academy as tough love designed to avoid his young charges becoming "failed athletes".
He claims to have tried to resolve the issue with the family amicably, but said they demanded an excessive settlement payment.
Ryu Jae-yool, the lawyer representing Kim, told AFP the case reflects a "culmination of years-long child abuse in disguise of a training method".
Son senior and his coaches are currently being investigated, and could face fines or, if deemed serious enough, the case will go to court, Ryu said.
"I expect Son to be indicted and tried at court," Ryu said, adding that this would "contribute to ridding the country of physical and verbal abuse against youth".
Separately, Kim's family have also reported Son senior to the state-run Korea Sport Ethics Centre for an investigation.
As part of the probe, authorities will question young players to determine if they have experienced verbal or physical abuse and will refer the case to law enforcement if wrongdoing is found.
