Ultimate Fighting Championship (UFC) lightweight champion Conor McGregor wasn’t always the biggest name in mixed martial arts (MMA), growing up as a rough-and-tumble kid on the streets of Crumlin in Dublin, Ireland.

Which he recently shut down.

But “Notorious” was able to elevate himself above the rank-and-file of street-fighting hooligans and transform himself into one of the top draws in combat sports, behind boxing icon and undefeated pugilist Floyd Mayweather.

As luck would have it, they’ll slug it out in the upcoming Showtime pay-per-view (PPV) extravaganza this Saturday night (Aug. 26, 2017) inside T-Mobile Arena in Las Vegas, Nevada, in what is scheduled to last 12 rounds at 154 pounds.

To bring fans a closer look at where McGregor came from, ESPN put together a “Notorious” look at his Irish upbringing in Crumlin, which features a conversation with the lightweight champ’s first trainer, who praised his former pupil for his boxing abilities.

For much more on the Mayweather vs. McGregor boxing match click here.