It's a shame that no one is talking about the skill Nasukawa showed in the fight: Good jab, nice straight right hand, excellent pivoting/movement, counter-punching skills, feints. That counter and pivot at 0:49 is a thing of beauty as is his boxing.
The weight difference made it a circus act but the boy is very talented.
But I still think the most likely explanation is that he was just beaten. He's a young man and was severely undersized on the night. The event may have also overwhelmed him. Exhibition or not, he was fighting Floyd Mayweather Jr.
The knockdowns did look a bit elaborate, but I can’t see any reason why the fight would be fixed - not in favour of Floyd humiliating the guy at least.
Tenshin is clearly an excellent fighter, and a relatively neat offensive boxer from the snippets we saw of him. He’s not an elite boxer at any weight though, and it should come as no surprise that a ATG fighter like Mayweather, which a large natural weight advantage, would demolish him.
I'm guessing his bank balance will be taking quite the deposit over the coming days. I'd hate to think how much Floyd got for this joke. He's making more money in single exhibition events than genuine world level boxers do in a career, it's crazy.
People seem to forget that when Mayweather fought from 130 to 135lbs he had something like a 70% KO/TKO rate and a lot of those guys he stopped were the best in the world at those weight classes. This time he was up against a teenager who competes at 120lbs in another sport and people are acting surprised at the devastating effect his punches had on the kid?