By Keith Idec

Fewer viewers watched the Leo Santa Cruz-Abner Mares rematch than their first fight.

Nielsen Media Research ratings released Tuesday revealed a peak audience of 633,000 tuned in to Showtime to see Santa Cruz beat Mares again in their 12-round fight for Santa Cruz’s WBA “super” world featherweight title Saturday night at Staples Center in Los Angeles. The second bout between Santa Cruz and Mares, Mexican-American rivals from Southern California, attracted an average audience of 600,000.

Santa Cruz (35-1-1, 19 KOs) defeated Mares (31-3-1, 15 KOs) by unanimous decision in a fan-friendly fight that drew rave reviews. All three judges scored their fight for Santa Cruz (117-111, 116-112, 115-113).

Their first fight, an entertaining encounter Santa Cruz won by majority decision in August 2015, was watched by a peak audience of 1,614,000 and an average audience of 1,217,000. That bout was broadcast by ESPN, which has a sizeable reach advantage over Showtime.

ESPN, a basic cable channel, is available in approximately 86 million homes in the United States. Showtime, a premium cable channel, has roughly 24 million subscribers in the U.S.

The opener of Showtime’s doubleheader Saturday night, Jermell Charlo-Austin Trout, drew slightly lower ratings than the main event between Santa Cruz and Mares.

Peak viewership for Charlo-Trout was 575,000. The average viewership for the Charlo-Trout bout was 532,000.

Houston’s Charlo (31-0, 15 KOs) dropped Trout twice, once apiece in the third and ninth rounds, on his way to topping Trout (31-5, 17 KOs) by majority decision. Charlo won their 12-round fight for his WBC super welterweight title on two scorecards (118-108, 115-111), while a third judge had it even (113-113).

Charlo-Trout aired mostly at the same time as the Terence Crawford-Jeff Horn fight was streamed live on the ESPN+ app. Nielsen Media Research doesn’t track viewership for ESPN’s new streaming service and ESPN hasn’t announced how many people watched Crawford-Horn.

Crawford (33-0, 24 KOs), of Omaha, Nebraska, stopped Australia’s Horn (18-1-1, 12 KOs) in the ninth round of a one-sided fight at MGM Garden Arena in Las Vegas to win the WBO welterweight title. The 30-year-old Crawford also became a world champion in a third weight class.

Crawford-Horn had concluded by the time the Santa Cruz-Mares rematch began.

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