In front of nearly 20,000 fans packed into the Staples Center, McGregor and Mayweather met on the dais for the first press conference that kicked off a four-city world tour to promote their fight.
Despite rumors about the match-up first going public more than a year ago, McGregor and Mayweather had never been in the same room together until Tuesday's press conference where they faced off in front of throngs of screaming fans.
McGregor was the first fighter to hit the stage with the crowd very much electrified by his arrival. The UFC lightweight champion stood stoic until he cracked a smile when hearing the announcement that Mayweather was going to join him at the press conference.
Mayweather seemed to enjoy a more grand entrance as he walked in with a huge entourage before stepping onto the stage where he came face-to-face with McGregor for the first time.
The two fighters stood just a few feet away from each other with Mayweather and McGregor both stone faced for a moment, but that didn't last long.
McGregor started chirping at Mayweather, who refused to engage in any kind of verbal warfare with the outspoken Irishman until they separated and the press conference got underway.
This is just the first of four times this week where McGregor and Mayweather will engage in a press conference that will be capped off by a similar face-off.
From here, McGregor and Mayweather will travel to Toronto on Wednesday, New York on Thursday, and then finally a stop in London on Friday before the fighters return to their respective camps to finish training for the next month.
It all leads to the historic showdown on Aug. 26 from the T-Mobile Arena in Las Vegas where McGregor will challenge Mayweather in one of the biggest fights in the history of combat sports.
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