It seems to happen every few years: a boxing superfight briefly jolts the fringe sport back into the public consciousness.
But the latest mega match-up – between an undefeated boxer coming out of retirement and a celebrated mixed martial arts fighter who has never entered a professional boxing ring – is without precedent.
It's projected that the August 26 bout between Floyd Mayweather Jr. and Conor McGregor will earn more than US$500 million through pay-per-view buys and just a little under $90 million through ticket sales.
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Yet there seems to be a consensus that this superfight will be far from super. It's been derided as a clash pitting "a caveman" against a "defensive genius," a contest in which McGregor "will not land a single punch."
The 29-year-old McGregor is one of the most magnetic figures in the history of mixed martial arts, the only Ultimate Fighting Championship fighter to simultaneous hold titles in two weight classes. On his way to the biggest payday of his career – potentially more than $100 million – he's younger, taller and boasts a longer reach than his opponent.
But McGregor is also a 0-0 boxer going toe to toe with a legend who is 49-0, has won championships in five weight classes and is one of the most elusive boxers to ever slip a punch.
Here's a look at the various factors that weaken McGregor's chances.