Elvis Rodriguez couldn’t be more familiar with the experienced ex-champion he will encounter Saturday night.

The Dominican southpaw sparred countless rounds versus Viktor Postol at Freddie Roach’s Wild Card Boxing Club in West Hollywood, California. Roach was the head trainer for Ukraine’s Postol and Rodriguez when they went at it all those times in his gym, but the International Boxing Hall of Famer will work Rodriguez’s corner for their “Showtime Championship Boxing” co-feature at The Cosmopolitan of Las Vegas.

Rodriguez, 27, has youth and activity on his side, but he anticipates a stiff test from the 39-year-old Postol, a former WBC super lightweight champion.

“Everybody knows we’ve done a lot of sparring,” Rodriguez told BoxingScene.com through a translator. “I know him very well. He [was] part of our team. He’s a great fighter and we’re expecting the best Postol. I’m ready for the best Postol on Saturday night.

“He’s definitely the biggest name and the most talented fighter I’ve fought up until this point in my career. [Beating him] would show the world that I’m here and I’m ready for the next level.”

Postol (31-4, 12 KOs) sparred with Rodriguez (14-1-1, 12 KOs) as recently as early in 2022, when Postol prepared to face undefeated Gary Antuanne Russell in another 10-rounder Showtime televised from The Cosmopolitan.

Russell was winning decisively on all three scorecards when referee Mike Ortega stepped between them to stop their fight with only 29 seconds remaining in the 10th and final round. Postol, who was on his feet at the time of the stoppage, lost by knockout or technical knockout for the first time in his 15-year, 35-fight professional career.

Postol protested the stoppage because he didn’t appear to be badly hurt.

“I think the ref jumped the gun a little bit,” Rodriguez said. “I’ve watched the fight a lot. I definitely think the fight shouldn’t have been stopped. It was a good fight. You can’t take anything from Gary Russell. He won that night, but I definitely don’t think the fight should’ve been stopped.”

Postol will fight for the first time in the 16 months since his loss to the hard-hitting Russell (16-0, 16 KOs).

Rodriguez is 3-0 since Kenneth Sims Jr. (20-2-1, 7 KOs) upset him by majority decision in their eight-rounder in May 2021 at Virgin Hotels Las Vegas. He hopes to become the first foe to stop Postol without any controversy in their 10-round, 142-pound bout Saturday night.

“That would be a huge plus for me,” said Rodriguez, who most recently edged Joseph Adorno (17-3-2, 14 KOs) by majority decision in a 10-rounder February 25 at The Armory in Minneapolis. “It would be big for my career and I think fans would really appreciate my ability to do something like that. But we’re ready to go the distance.”

Rodriguez-Postol was supposed to open Showtime’s tripleheader Saturday night. Their fight was elevated to the co-feature Wednesday, when the original co-feature, a WBC bantamweight championship bout between Nonito Donaire and Alexandro Santiago, was shifted to Showtime Pay-Per-View’s Errol Spence Jr.-Terence Crawford undercard July 29 at T-Mobile Arena in Las Vegas due to injuries sustained by boxers who were scheduled to compete on the Spence-Crawford card.

Detroit native Frank Martin (17-0, 12 KOs), an emerging lightweight contender, will square off against Armenia’s Artem Harutyunyan (12-0, 7 KOs) in Showtime’s 12-round main event. The telecast is scheduled to begin at 10 p.m. EDT (7 p.m. EDT) with a 10-round welterweight bout in which Las Vegas native Freudis Rojas (10-0, 10 KOs) will meet Mexico’s Diego Sanchez (19-2, 16 KOs).

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