He’s been labelled a drug cheat after serving a three-month suspension in 2014 for using a prescribed medication to treat a heart condition, saying he was unaware it had been added to the banned list.
Sun triggered a diplomatic row with Japan at the last Asian Games four years ago when he petulantly branded their national anthem “ugly”.
He has also irked Chinese officials with his sponsorship deals and once spent a week in a detention centre for a driving offence.
But Sun carries on, unfazed by all the kerfuffle and seemingly revelling in his reputation as swimming’s bad boy.
To those who know him best, nothing could be further from the truth. Sun’s part-time coach believes the Chinese superstar is a gentle giant.
“He’s actually a very sensitive guy,” said Denis Cotterell. “He’s very emotional and he gets upset by a lot of the things that are said and written about him because a lot of it just isn’t true.”
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