Floyd Mayweather
Mayweather laughing at McGregor in his latest dig at the UFC icon Getty

Floyd Mayweather Jnr has aimed another shot at Conor McGregor, offering $10,000 (£7,984) to anyone who can provide the best caption to images of the UFC champion tapping out.

Mayweather and McGregor have continued to exchange barbs with both men fuelling speculation over a multimillion dollar showdown between the two inside a boxing ring.

Reigning UFC lightweight champion McGregor was recently granted a licence permitting him to box in the state of California, a move the Mayweather camp described as a "con job" from the Irish fighter to "keep his name alive".

Following those comments, the retired boxing icon has now posted a video on Instagram of the final moments of McGregor's UFC 196 defeat to Nate Diaz in March 2016 – the Dubliner's only loss in the promotion.

McGregor was forced to tap out after being locked in a brutal rear-naked chokehold, with Mayweather gleefully replaying that moment over and over. The message "49-0 vs Conor the notorious quitter" then flashes up, a nod to the 39-year-old's unbeaten record in the ring.

The social media post also offers fans the chance to profit from the latest dig, with an attached message reading: "CAPTION THIS! Best caption wins $10,000. The winner will be announced on Monday, Dec 19. Stay tuned."

McGregor is currently on a break from UFC until after the birth of his first child, with UFC president Dana White not expecting the 28-year-old to return to the Octagon until late 2017.

Obtaining a boxing licence at the beginning of December ignited talk of a showdown with Mayweather, although five-weight world champion Mayweather has dismissed the move as nothing more than a ploy to keep his name in the headlines while he is inactive.

Mayweather told Fighthype: "I don't fight in California, what did he get a licence in California for? I'm [going] to tell you like this, he's blowing smoke up everyone's a**. He doesn't really want to fight because I went to his boss.

"He doesn't really want to fight. He's just doing that to keep his name alive, you know what I'm saying, to stay relevant. He don't really want to fight. He's doing that, building his followers, but he's smart."