Boxing legend Floyd Mayweather and mixed martial arts icon Conor McGregor confirmed plans for a long-awaited showdown on Wednesday, triggering both criticism and anticipation for what is set to be one of the richest fights in history.

Mayweather and McGregor - kingpins of their sports - will climb into a boxing ring to face each other at Las Vegas's T-Mobile Arena on August 26. The 40-year-old Mayweather will be aiming to reach the 50-0 milestone while McGregor is a heavy underdog in the 12-round boxing match. A victory for the Irishman would be a monumental upset.

Leonard Ellerbe, chief executive of Mayweather Promotions, said the boxer's team decided to end his 23-month retirement because the clamor for the 154-pound showdown had been impossible to ignore. The event is expected to be a pay-for-view blockbuster, and organizers are hoping it can challenge the 4.6 million pay-per-view buys for Mayweather-Pacquiao.