McGregor, 29, became the first UFC fighter to hold two belts simultaneously and has confidently predicted he will floor Mayweather within four rounds to dent his flawless record.
"I'm sure he has", McGregor said.
McGregor also took a swipe at Mayweather's defensive techniques.
Horn immediately went after Mayweather following his victory over Pacquiao, asking if he was interested in a real fight instead of the upcoming stunt with McGregor. Boxing has been dear to my heart my whole, entire life. This is the biggest fight of my career so far and I'm going to do a number on Badou Jack on August 26'. I'm impressed. You gotta respect the guy. On paper, everything leans toward Conor McGregor.
"I'm scheduling bouts with opponents, telling them what I'm going to do to them and how I'm going to do it". Tell me how his temple looked.
"It means the world to have fans travelling from Ireland and all over the world for this fight".
There were also tweets from folks saying tickets could be purchased at Costco, which doesn't help those of us without an extra $3,500 after cases of the toilet paper and ginger ale are secured. I didn't release no connecting to the face shots, I didn't release no footage of him getting slapped around because he got slapped around, Ariel, he got badly, badly slapped around. This isn't a damn Rolling Stones concert that's going to sell out in seconds. We thought the worst was about to happen.
"For all the people who think @TheNotoriousMMA can't box".
Mayweather arrived the gym in style. The gate appears just fine.
When asked during a media scrum if he agrees McGregor, who has never boxed professionally before, will "win" in some ways if he's able to last 12 rounds with the all-time great, Mayweather quickly agreed.
The referee for Mayweather-McGregor will be particularly important because McGregor, a UFC superstar, will make his pro boxing debut and is expected to make their fight physical and rough to diminish Mayweather's advantages as the vastly superior boxer.
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