Golden Boy putting on free card night before Canelo-Khan

Petr Petrov, the 2014 Boxcino lightweight tournament winner, will headline a card in Las Vegas on May 6. Banner Promotions

The Canelo Alvarez-Amir Khan middleweight championship fight on May 7 (HBO PPV) at the T-Mobile Arena in Las Vegas is the centerpiece to the Cinco de Mayo boxing weekend, and Golden Boy Promotions announced the addition of another card that weekend on Tuesday.

On May 6, the night before Alvarez-Khan, Golden Boy will put on a special three-hour card on Estrella TV at the T-Mobile Arena's outdoor Toshiba Plaza. The card begins immediately following the Alvarez-Khan weigh-in, which will also be at the Toshiba Plaza, adjacent to the new arena. And get this: Admission to fight card is free. The card begins at 7 p.m. ET with the telecast going on the air at 9 p.m. ET.

In the main event, Mexican lightweight Marvin Quintero (28-6, 24 KOs), a former world title challenger, and Spain-based Russian Petr Petrov (36-4-2, 17 KOs), who won the 2014 ESPN Boxcino lightweight tournament, will meet in a 10-round bout.

In the c-feature, Mexican junior welterweight Pablo Cesar Cano (29-4-1, 21 KOs) will face Alan Sanchez (17-3-1, 9 KOs), of Fairfield, California, in a 10-rounder. Opening the telecast, Mexico's Horacio Garcia (30-1-0, 22 KOs) will face an opponent to be determined in a 10-round junior featherweight bout.

"Golden Boy Promotions is giving back to all the boxing fans in Las Vegas and kicking off Cinco de Mayo weekend on May 6 with an action-packed night of free boxing to get everyone warmed up for Canelo versus Khan," Golden Boy CEO Oscar De La Hoya said. "Golden Boy is committed to bring the best in boxing, and the fights featured on May 6 are guaranteed non-stop action between fighters in their prime battling for [regional] titles that will get them closer to becoming the next world champions."