Jermell Charlo and Brian Castano drew Showtime’s biggest audience for live boxing in nearly three years Saturday night.

Nielsen Media Research released figures Tuesday that indicated an average audience of 756,000 watched their fantastic “Fight of the Year” candidate. Showtime’s audience peaked at 832,000 during a 154-pound title unification rematch that Charlo won by 10th-round knockout at Dignity Health Sports Park in Carson, California.

Those numbers were the highest for Showtime since Deontay Wilder’s first-round knockout of Dominic Breazeale in May 2019 at Barclays Center in Brooklyn. Wilder’s spectacular stoppage of Breazeale attracted an average audience of 795,000 on Showtime’s linear channel and a combined average viewership of 886,000 on Showtime’s linear channel and streaming service.

There wasn’t time for that audience to grow because Wilder needed just two minutes and 17 seconds to knock out Breazeale, who was the mandatory challenger for Wilder’s WBC heavyweight title.

Streaming viewership for the Charlo-Castano rematch wasn’t available as of Tuesday afternoon. Paramount Global, the parent company of Showtime and, doesn’t typically release streaming numbers, which are not tracked by Nielsen.

Nevertheless, viewership Saturday night easily surpassed Showtime’s most-watched boxing main event of 2021 – the controversial 12-round split draw between Charlo and Castano last July 17 from AT&T Center in San Antonio. Their first fight drew an average viewership of 422,000 and a peak viewership of 536,000.

Their rematch Saturday night was even more fan-friendly than their initial action-packed encounter.

Charlo, who fought effectively off his back foot throughout their bout, and an aggressive Castano exchanged flush punches on numerous occasions before Charlo sent Castano to the canvas twice during the 10th round. The taller, stronger Charlo made adjustments and eventually broke down Castano in what was a high-level, closely contested bout before Charlo began building a sizable lead during the final few rounds.

Ahead 89-82, 88-83 and 87-84 through nine rounds, Charlo landed a left hook that knocked Castano to one knee with 52 seconds to go in the 10th round. Castano answered referee Jerry Cantu’s count at five, but Charlo capitalized by attacking his vulnerable opponent.

A left uppercut to Castano’s head and a left to his body sent Castano to his gloves and knees a second time, with 34 seconds to go in the 10th round. Cantu called an end to their 12-round rematch at 2:33 of the 10th round as Castano struggled to reach his feet a second time.

Houston’s Charlo (35-1-1, 19 KOs) defended his IBF, WBA and WBC 154-pound championships and won the WBO junior middleweight title from Buenos Aires’ Castano (17-1-2, 12 KOs). Charlo also became just the seventh undisputed champion in any division during boxing’s four-belt era.

Earlier Saturday night, an average of 450,000 viewers tuned in for Showtime’s co-feature – rising welterweight star Jaron Ennis’ second-round knockout of previously unbeaten Custio Clayton. Philadelphia’s Ennis (29-0, 27 KOs, 1 NC) landed a right hand to the top and back of Clayton’s head that left Canada’s Clayton (19-1-1, 12 KOs) unable to continue after he beat referee Ray Corona’s count.

Keith Idec is a senior writer/columnist for He can be reached on Twitter @Idecboxing.