BOXING legend Floyd Mayweather is doing 2am sparring sessions as he continues to tease an incredible return to the sport.
The Money's last official fight was a 10th-round stoppage of Conor McGregor, who made a crossover from UFC.
That took Mayweather to 50 fights undefeated over the course of his 21-year professional career.
Since then, he has only faced Tenshin Nasukawa in an exhibition bout which saw him stop the Japanese kickboxer in two rounds.
Yet the 43-year-old continues to train hard, and one sparring partner believes he could "100 per cent come back".
Super middleweight Denis Douglin, 32, was called up by Mayweather for a sparring session, and was left surprised not just with the timing, but also Mayweather's fitness.
In an interview via , Douglin said: "He called me up around 1am. I know he likes to train at night. So I got up and told my mother that Mayweather wanted to spar.
"We got to the gym before him, I was walking around taking pictures and stuff. He walked in at 2am with so much energy and so excited, and he let me know that he was going to beat me up.
"He was making fun of me saying harmless stuff like: ‘Oh, you think you're so bad, you got all of those muscles, but I’m still going to beat you up’.
"I thought as much as I look up to this man I can't wait to get into the ring and put it on him.
"And I love the fact that he was excited to beat me up, it was like an honour to have Mayweather talking bad about me.
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"The first three rounds were great work, still talking trash back and forth to each other, and then in the fourth round he said: ‘let's turn the bell off, we're going to spar until you quit’."
Douglin, who has 22 wins and seven defeats from 29 pro fights, insists he didn't "quit", and the two enjoyed another 30 minutes trading blows.
The New Yorker added: "The last time we sparred was probably three years ago for his exhibition match in Asia and I kind of felt like he was slowing down a little bit.
"This time he felt sharp, he felt strong, his stamina was great. It was almost like he's getting better. Everything that he’s going through in his life is making him more focused on boxing.
" I think he could still hang with the top guys. There's no reason to try because he's already proven himself, but if he wanted to, he could still do it."
MCGREGOR REMATCH?
A rumoured money-spinning rematch against McGregor has long been on the cards for the global superstars.
Indeed, McGregor fuelled speculation further by goading Mayweather online to mark the third anniversary of their spellbinding bout.
The Irishman wrote: “Three years ago today I carried Floyd for his final boxing match.
“Wow time flies when you’re stacking cheddar. Happy retirement champ.”
Mayweather revealed he was keen for another fight after McGregor stepped back from the UFC in June, saying: “If I’m not mistaken, didn’t you tell Mike Tyson you could beat me if we fought a second time?
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“Now you’re quitting! I thought you wanted to beat the best? Well, if you decide to come back, I will be waiting to punish you again.”