The announcement on Monday in Tokyo (Sunday in the U.S.) that Floyd Mayweather would fight on New Year’s Eve against a Japanese kickboxer less than half his age and 25 pounds lighter was a stunner.

But Mayweather’s announcement on Instagram on Wednesday was the true bombshell.

After sitting at a news conference, answering questions about a fight with Tenshin Nasukawa and then posing for pictures with the 20-year-old rising star, Mayweather took to social media on Wednesday to say he’d been conned.

I don’t know about him, but I know this: Fight fans have been conned. The fans who have faithfully supported him for years have been conned.

This seems like some kind of a set-up for him to get attention for an event that would get very little in exchange for some easy money.

On Instagram, Mayweather said he was asked to fight a three-round exhibition match. He said it was supposed to “be an exhibition put on for a small group of wealthy spectators for a very large fee.” He said he was blindsided by what happened.

Yeah, right. I call total B.S. on this one.

Mayweather is hardly a shrinking violet and he has never — ever — failed to speak up on his own behalf since he became a professional boxer. Yet, if you believe his Instagram post, he wants you now to believe he remained silent and participated in the news conference as if it were a fight he’d agreed to simply to be courteous.

Again, one would have to be a fool to believe this.

Mayweather’s former promoter, Bob Arum, has been dogged for years about a line he made during an argument with a friend. Arum and a friend were out drinking one night and debating the merits of one fighter versus the other. The next night, when they picked it up again, Arum apparently took the other side.

When his friend called him on the contradiction, Arum said, “Yesterday I was lying. Today I’m telling the truth.”

That is exactly what Mayweather seems to be saying: Yesterday I was lying when I attended a press conference and answered questions and talked about Nasukawa’s skillset. Today, I’m telling the truth when I said there was never any intention for me to fight this guy.

The problem with Mayweather’s version of events is that over the last several months, he’s posted numerous photos of himself in Japan, including one with Manny Pacquiao. That’s led to speculation that Mayweather and Pacquiao will rematch sometime next year.

Given this farce with Rizin, it’s hard to believe anything Mayweather says now.

He said he didn’t speak up out of respect to the fans who flew to Japan for the news conference. But isn’t it even more disrespectful to let them believe you’re going to do something while you’re in their presence and then tell them you’re not when you are elsewhere?

On his Instagram post he wrote, “For the sake of the several fans and attendees that flew in from all parts of the world to attend this past press conference, I was hesitant to create a huge disturbance by combating what was being said and for that I am truly sorry.

“I am a retired boxer that earns an unprecedented amount of money, globally, for appearances, speaking engagements and occasional small exhibitions.”

This is beyond suspicious and seems like a con job to help boost the Rizin show in exchange for a nice check.

Until I see evidence to the contrary, that’s what I’ll choose to believe.

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