It is IMPOSSIBLE to say definitively that an athlete has or has not used steroids without testing (although it is down to the athlete to prove that he is clean not the other way round). You don't know nigel Benn, You weren't in his training camps etc etc
The ONLY way to stop accusations like this happening is to bring proper random blood testing into the sport, then issues like this will never arise.
Blood on a boot 15 years later is a complete farce and I highly doubt anything will come of this. But had proper testing been done at the fight Benn wouldn't have to clear his name of this slur now.
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