Chris Colbert upset by late replacement Hector Garcia; Viktor Postol stopped in 10th

Chris Colbert, ESPN's No. 2-ranked 130-pounder, was slated to challenge for his first world title on Saturday. But after the champion, Roger Gutierrez, tested positive for COVID-19, Colbert (16-1, 6 KOs) was set to stay busy against unheralded late replacement Hector Garcia.

In the PBC on Showtime's main event, Colbert, a -2200 betting favorite at Caesars Sportsbook, was dominated by Garcia in a major upset on Saturday in Las Vegas.

Garcia (15-0, 10 KOs) took the fight to Colbert from the opening bell and floored him in Round 7 with a crisp left hand. He went on to take a unanimous-decision victory via scores of 118-109, 119-108 and 118-109.

Colbert won Round 3 unanimously and Round 9 on two of three cards. Garcia swept the rest of the rounds and outlanded Colbert 211-116.

With the defeat in the title eliminator, Colbert lost his title opportunity while Garcia guaranteed himself a fight with Gutierrez.

"Tonight he was the better man," said Colbert, who suffered the first defeat of his pro career. "I want to run it back. ... I take my losses like I take my wins."

Colbert, a 25-year-old fighting out of Brooklyn, New York, headlined his third consecutive Showtime card. Al Haymon's PBC invested a lot of time into building Colbert, but now it's Garcia who will vie for the title.

The 30-year-old Dominican accepted the fight on two-and-a-half-weeks' notice and had never competed on the top level before.

Russell defeats Postol by late TKO

In a career-best performance, Gary Antuanne Russell scored a 10th-round stoppage over former champion Viktor Postol in a step-up fight at 140 pounds.

The younger brother of former champion Gary Russell Jr., Russell (15-0, 15 KOs) was ahead on all three scorecards at the time of the stoppage: 88-83, 89-82 and 89-82.

While the 25-year-old was on his way to victory, referee Mike Ortega's decision to halt the fight was highly questionable. There were just 29 seconds remaining in the fight, and Postol appeared stunned after a barrage but not in serious trouble.

Postol's (31-4, 12 KOs) other losses came against Terence Crawford, Josh Taylor and Jose Ramirez via decision. His wife and 5-year-old twin sons remain in Ukraine, which is under attack by Russia. Postol told BoxingScene on Thursday he planned to fly to Poland or Romania and then drive over the border to be with his family by Monday. He lives in Brovary, a suburb of Kyiv, the Ukrainian capital.

"I just couldn't do what I wanted to do in the ring," Postol said. "My legs were not there and my arms were not there like I needed them to be. I've fought much better fighters than Gary Russell, but for some reason, I wasn't able to perform to my abilities. I came here to win tonight. Unfortunately, I wasn't able to achieve my goal."

Martinez ends Ancajas' title reign

Jerwin Ancajas, a 115-pound titleholder since 2016, was upset by Fernando Martinez in the 10th defense of his championship.

Martinez, a 30-year-old fighting out of Buenos Aires, Argentina, prevailed via unanimous decision by scores of 117-111, 118-110 and 118-110 in a hellacious action fight.

Martinez (14-0, 8 KOs) was making his U.S. debut. He had never competed on the world-class level before Saturday.

Ancajas (33-2-2, 22 KOs) was rated No. 5 by ESPN at junior bantamweight. The 30-year-old Filipino landed just 192 shots, while Martinez set a CompuBox record for the division by landing 421.