Sid Khan joined Earlsfield ABC as an 11-year-old growing up in nearby Tooting -- he is now the London boxing club's head coach.
Sid Khan joined Earlsfield ABC as an 11-year-old growing up in nearby Tooting -- he is now the London boxing club's head coach.
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Khan (middle) is flanked by winning fighters Joe Joyce (L), Kirk Garvey (C) and Louis Adolphe (R) after a victorious night for Earlsfield at the 2012 ABA Elite Championship Finals at York Hall in east London.
Khan (middle) is flanked by winning fighters Joe Joyce (L), Kirk Garvey (C) and Louis Adolphe (R) after a victorious night for Earlsfield at the 2012 ABA Elite Championship Finals at York Hall in east London.
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His younger brother, London mayor Sadiq Khan (center), also trained at Earlsfield before becoming a lawyer and then politician.
His younger brother, London mayor Sadiq Khan (center), also trained at Earlsfield before becoming a lawyer and then politician.
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Sadiq Khan (middle) still regularly visits Earlsfield ABC, where his brothers and nephews are fixtures. This photo of Khan with young prospects hangs on the wall of the club.
Sadiq Khan (middle) still regularly visits Earlsfield ABC, where his brothers and nephews are fixtures. This photo of Khan with young prospects hangs on the wall of the club.
CNN
The Khans' late father drove the No. 44 bus, which is seen passing the Henry Prince Estate in south London, where the boys grew up.
The Khans' late father drove the No. 44 bus, which is seen passing the Henry Prince Estate in south London, where the boys grew up.
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Joyce (L) represented Britain at the Rio 2016 Olympics but lost a controversial super heavyweight gold medal match to Tony Yoka of France. Sid Khan is critical of amateur boxing's reformed scoring system, along with the removal of headgear and the introduction of professionals into the Olympics.
Joyce (L) represented Britain at the Rio 2016 Olympics but lost a controversial super heavyweight gold medal match to Tony Yoka of France. Sid Khan is critical of amateur boxing's reformed scoring system, along with the removal of headgear and the introduction of professionals into the Olympics.
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Joyce -- here celebrating a 2015 World Series of Boxing win with a backflip -- entered Earlsfield ABC Club as an inexperienced fighter at the age of 22. He became the European and Commonwealth champion before earning an Olympic silver medal, aged 31.
Joyce -- here celebrating a 2015 World Series of Boxing win with a backflip -- entered Earlsfield ABC Club as an inexperienced fighter at the age of 22. He became the European and Commonwealth champion before earning an Olympic silver medal, aged 31.
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Populas Khan -- Sid and Sadiq's youngest brother -- is sent to his corner to receive treatment during an amateur boxing night in 2011. The Khans come from a family of seven brothers, all of whom boxed at Earlsfield.
Populas Khan -- Sid and Sadiq's youngest brother -- is sent to his corner to receive treatment during an amateur boxing night in 2011. The Khans come from a family of seven brothers, all of whom boxed at Earlsfield.
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Populas (R) still boxes occasionally and is also a trainer at Earlsfield.
Populas (R) still boxes occasionally and is also a trainer at Earlsfield.
CNN
The club opens its doors to amateur boxers of all different levels and both sexes, four days a week. Here, Sid Khan tapes the gloves of a young fighter while offering words of advice.
The club opens its doors to amateur boxers of all different levels and both sexes, four days a week. Here, Sid Khan tapes the gloves of a young fighter while offering words of advice.
Motez Bishara
The club's boxers usually train for 11 hours a week.
The club's boxers usually train for 11 hours a week.
Dan Hodge / CNN
All of them have the goal of boxing for Great Britain, according to Sid Khan. "Once you're in the ring, you're boxing for your country," he said.
All of them have the goal of boxing for Great Britain, according to Sid Khan. "Once you're in the ring, you're boxing for your country," he said.
Dan Hodge / CNN