The man being hailed as 'The McGregor Slayer', Joeseph Duffy, was the last man to stop Conor McGregor at Cage Warriors Fighting Championships 40 in 2010.
'Irish Joe' used his grappling skills to catch McGregor with a savvy arm-triangle choke in the opening round, becoming the second man to conquer 'The Notorious' in the cage. Artemij Sitenkov also caught the interim featherweight champion with a submission in 2008.
In an interview with MMAJunkie on Wednesday, McGregor said he'd love to see 'journeyman' Duffy climb the lightweight ranks so he could knock him out in a rematch.
"I'd love to see Duffy climb that rank; do I think he has it in him? I don't. I think he's a journeyman," McGregor said. "I would love to see him climb up, and I would KO him stiff just for the way this has all panned out."
After losing to Ivan Musardo in 2011, Duffy switched to professional boxing and went undefeated as a 7-0 prospect. The 27-year-old returned to MMA in 2014, but McGregor feels as though he's a quitter.
"He quit the sport. He moved country. He changed teams. He was Welch Joe. Then he's London Joe. Now he's Canadian Joe. Then he's sees my success, and all of a sudden he's Irish Joe"
Duffy will look to earn his third win under the UFC banner when he takes on Dustin Poirier on October 24th at UFC Fight Night 72. McGregor will meet Jose Aldo in a title-unification bout at UFC 194 on December 12th.
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