By Sarah Berkowitz

Here’s everything you need to know about tonight’s big fight:

When and where is it? Tonight in Las Vegas at the T-Mobile Arena, which was also the site of the McGregor—Mayweather circus/bout. The arena is sold out.

Coverage starts at 8 p.m. Eastern on HBO pay-per-view. The main event is expected about 11 p.m. The fight costs $69.95, and $10 more for HD. Jim Lampley, Max Kellerman and Roy Jones will call it.

The fight is also distributed by the promoter through streaming atringtv.com.

Who is Canelo Álvarez? At 27, Álvarez is 49-1-1, his only loss coming to Floyd Mayweather, who you may have heard of. Among the fighters he has vanquished are Shane Mosley, Miguel Cotto, Amir Khan, and most recently Julio Cesar Chavez Jr. He is one of Mexico’s most popular athletes. And with the fight occurring on Mexican Independence Day, his fans may have even more to celebrate.

Who is Gennady Golovkin? A ruthless 35-year-old Kazakh who is 37-0, with a series of brutal knockouts that have made him a sensation. Golovkin punches as hard as a fighter 15 pounds bigger, ESPN found. His last fight, against Daniel Jacobs, was an unconvincing decision, putting a few doubts in some fans’ minds.

Is there a belt on the line? Golovkin holds the IBF, WBA, and WBC middleweight titles.