That Mayweather would deign to step into the ring with McGregor at all is a sign of how far MMA, and McGregor in particular, has come over the past few years.
Google Trends data show that search interest in McGregor is higher this year so far than it is for Mayweather in all but 12 countries for which there are data available.
Mayweather is not even safe in his own back yard of America, where interest in the brawling Irishman has built up a head of steam over the past two years.
This makes McGregor unique for a professional fighter in terms of the amount of hype he can drum up, magnified by the fact that he appeals to a slightly different audience.
Interest in the fight peaked last month during the two fighters' press-conference tour in Los Angeles, Toronto, New York and London in just a few days. In this sense it did its job. An exhibition of the worst kind of posturing it may have been - Mayweather accused McGregor of racism and used a homophobic slur in a few seconds - but it is very likely to have increased the TV viewer numbers for the fight.
In poor taste? Yes, but Mayweather vs McGregor will prove to be a great success in one of the measures that the two competitors care most about: money.