So today is the day of one of the most eagerly anticipated and certainly most hyped fights of recent years.

Irish Mixed Martial Arts (MMA) two time champion Conor McGregor takes on Floyd Mayweather, the undefeated boxing legend in Las Vegas in the first major cross-discipline clash of its kind. McGregor is the highly quotable motor-mouth fighting pride of Dublin, with over 24m followers across his Twitter, Facebook and Instagram accounts.

There have been countless articles written in the last week about how both Mayweather and McGregor are master media manipulators, and undisputed heavyweights of hype. The numbers behind this fight would bear this out - an anticipated global audience of 5m pay per view watching and an estimated £700m in ticket sales, pay per view and ancillary revenues.

This article from Business Insider uses engagement rates on Conor McGregor's social media channels to show how marketable he is as a sports star. And at first glance this all seems very impressive - 400k retweets of a tweet to announce the bout sounds like an impressive rate of engagement from an account which has had between 4m and 5m followers since this announcement.

However, retweets do not dollars make. And Conor McGregor clearly wants to use this fight as a promotional platform for his own brands - AugustMcGregor, his clothing line with designer David August, and McGregor Fast, his online subscription-based fitness programme. Despite numerous tweets throughout the build-up to the fight including the "handles" of both of the Twitter accounts for these brands they currently (at time of writing) have 1,905 and 7,603 followers respectively. For a man with over 5.6m followers on Twitter, that's not a particularly impressive engagement or conversion rate.

The fight has not yet started, and if McGregor pulls off what almost all pundits say would be a miraculous victory, he would be catapulted to new levels of notoriety and all bets would quite literally be off. But for now, I'd say "don't believe the hype".