'Greatest businessman ever': Reaction as Mayweather bags '$64k a second' for destruction of Nasukawa

Floyd Mayweather's quickfire knockout of Tenshin Nasukawa at Rizin 14 drew plenty of reaction online after the American blitzed the Japanese kickboxing sensation in the first round in Saitama.

The fight, which served as the main event of the Japanese mixed martial arts promotion Rizin's New Year's Eve spectacular, was billed as a boxing exhibition, with Mayweather himself stressing the point throughout the lead-up to the eagerly-awaited matchup.

But when it came around to fight night, "Money" Mayweather was all business as he dropped the Japanese kickboxer three times en route to a first-round TKO victory.

Asian combat sports correspondent James Goyder criticized the contest, saying there was little to no relevance in matching Mayweather with Nasukawa, and suggesting Mayweather's quickfire win could easily have been achieved by "thousands of 154lb boxers."

The fight was a mismatch from the start, with Mayweather significantly outweighing his young opponent, and having a monumental experience advantage in boxing.

© Reuters / Issei Kato

Nasukawa was undefeated as a kickboxer, but with his major weapons - his kicks - rendered illegal, he was effectively a sitting duck for 50-0 boxer Mayweather, who finished the fight as easily as many expected, given the rules.

Some fans not-so-secretly hoped Tenshin would throw the rules out of the window and make a huge name for himself globally by attempting to knock out Mayweather with a head kick, one of his trademark kickboxing strikes.

© Reuters / Issei Kato

But with his hands - well, his feet - tied with a contractual threat of a multi-million-dollar fine, Nasukawa stuck to the rules, and was comprehensively outgunned by the boxing icon.

While it was an embarrassing defeat for Nasukawa, who was comprehensively dismantled by the multiple world champion, it was also rated a major embarrassment for promoters Rizin, who saw one of their biggest superstars humiliated in double-quick time.

Nasukawa was devastated after the defeat, with tears streaming down his face following his humiliating first-round loss.

But there was a word of encouragement for the defeated Nasukawa from former UFC title challenger and fight analyst Dan Hardy, who used a Harry Potter reference to lift the young Japanese star's spirits.

Some simply picked up on the lucrative payday Mayweather will pocket from his night's work - said to be $9 million - hailing him as "the greatest businessman ever."