Mayweather | McGregor press tour kick off

Floyd Mayweather Jr., left, and Conor McGregor have to be separated by UFC president Dana White after standing toe to toe at a promotional stop at Staples Center on Tuesday.

Floyd Mayweather Jr. at Staples Center on Tuesday.

Conor McGregor is introduced at Staples Center on Tuesday.

Floyd Mayweather Jr. during a press conference at Staples Center on Tuesday. Mayweather and Conor McGregor embark on a four-city international press tour.

Conor McGregor during a press conference at the Staples Center on Tuesday. Floyd Mayweather Jr. and McGregor embark on a four-city international press tour.

Floyd Mayweather Jr., left, and Conor McGregor, far right, at Staples Center on Tuesday.

Conor McGregor during a press conference at Staples Center on Tuesday.

Floyd Mayweather Sr. defends his son Floyd Mayweather Jr. while getting into a shouting match with Conor McGregor (not pictured) during a promotional stop at Staples Center on Tuesday.

Floyd Mayweather Jr. and Conor McGregor take the steage at Staples Center on Tuesday to open their four-city international press tour.