Conor McGregor, right, gets into it with Floyd Mayweather Jr. (Jae C. Hong/Associated Press)

Conor McGregor and Floyd Mayweather Jr. staged their first joint promotional appearance Tuesday for their Aug. 26 fight, and the UFC star was ready for the show. McGregor promised a quick knockout, mocked Mayweather’s tax-bill issues and even wore a suit decorated with tiny f-bombs.

However, McGregor also made a comment to Mayweather that many found offensive, and it raised anew criticism of the Irishman for allegedly racist behavior. With Mayweather doing some shadow boxing onstage at Los Angeles’s Staples Center, McGregor yelled at him, “Dance for me, boy!”

Possibly sensing that he had crossed a line, McGregor quickly changed his comments to, “Dance for me, sir. Dance for me!” However, that did little to allay the negative reception online for his choice of words, especially as some thought McGregor said “son” and not “sir.”

This isn’t the first time McGregor has been accused of racism, particularly during pre-fight news conferences. At a similar event in 2016, he called Nate Diaz a “cholo gangster from the hood,” and later in the year he called Diaz and his brother Nick, another MMA fighter, “cockroaches.”

Before a 2015 matchup with Brazil’s Jose Aldo, McGregor said, “What I really want to do is turn his favela into a Reebok sweatshop. They work well over there.” Earlier this year, he referred to a chocolate-covered candy when he described Mayweather as “a Malteser with eyeballs.”

For his part, Mayweather called McGregor a “b—-” Tuesday, during an event that featured the antagonists dropping numerous profanities on each other. McGregor even went so far as to have a profane phrase stitched into his suit, in a way that looked simply like pinstripes from a distance. (Warning: explicit language found in the below photo.)

This was the first stop in a four-city, three-country media tour to promote the fight. McGregor and Mayweather are set to continue trading verbal jabs this week in Toronto, New York and London, and while the Irishman can be counted on for more attention-grabbing commentary, it remains to be seen if he opts to choose some of his words more carefully.