Merton's top policeman has revealed the unsolved murder of a family member led him into the police service – and the boxing ring with a two-times world heavyweight champion.

Borough commander Detective Chief Superintendent Darren Williams will be squaring up to former heavyweight Tim Witherspoon later this year for a charity bout in support of the Royal Marsden Hospital.

While Detective Chief Superintendent Williams admits he is "hopelessly unprepared" and has "no realistic chance of winning", he does have experience boxing in the army and a family history with an impressive boxing heritage.

His great uncle, Ben Taylor, was an amateur boxer who fought former world heavyweight boxing champion, Jack Johnson, in 1908.

He said: "Despite the fact that no other fighters would fight Jack, my great, great uncle agreed to do so and on July 31, 1908 in Plymouth, despite being hopelessly unprepared and with no realistic chance of winning, Ben fought Jack for the world heavyweight title.

"Ben was floored 10 times before finally being knocked out by a fierce right to the chin."

Eight years later, on Boxing Day, Mr Taylor was found dead in Custom House, London, his skull crushed.

Det Ch Supt Williams added: "No-one was ever caught and the details of his death remain a mystery.

"It one of the reasons that I became a policeman, the fact that someone had killed a relative of mine but had never been caught."

The pair will square up on October 12 at the Wellington Barracks, in Birdcage Walk, to raise money for the Royal Marsden Hospital and a children's cancer charity with tickets priced at £200.

To register interest in tickets email: marsdenboxing@aol.com.

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