Jose Valenzuela revealed that he felt depleted physically before he stepped into the ring to face Chris Colbert on March 25.

The 24-year-old lightweight informed BoxingScene.com during a recent interview that he had surgery for an unspecified injury two weeks before he boxed Colbert on the David Benavidez-Caleb Plant undercard at MGM Grand Garden Arena in Las Vegas. Valenzuela wouldn’t divulge the nature of his injury, but he said he suffered an accident that required a procedure late during training camp and felt “fatigued” during their 10-round fight from medication he took after the surgery.

Valenzuela (12-2, 8 KOs), who will battle Colbert again Saturday night, dropped Colbert (17-1, 6 KOs) with a counter left a little less than 30 seconds into their Showtime Pay-Per-View fight. Colbert got up, effectively utilized his jab to get back into their fight and narrowly won by the same score, 95-94, on the cards of judges Glenn Feldman, Lisa Giampa and Don Trella.

Valenzuela believes he would’ve been able to finish off Colbert if he had more energy that night.

“I was like in a little accident, so I was in no condition to fight two weeks before my fight,” Valenzuela said. “So, I think that played a major role. I had surgery two weeks before my fight, but I didn’t wanna put none of that out there because I knew he wouldn’t wanna take the fight maybe if he knew.”

The Mexican southpaw didn’t consider pulling out of their bout because he felt it was an opportunity he couldn’t squander coming off his surprising third-round knockout defeat to Edwin De Los Santos in his previous appearance in September 2022.

“Where I come from, you don’t get many opportunities like these, so I was gonna make the most of it,” Valenzuela said. “I knew I had enough heart and will to win the fight. And you look at my frame that night, I looked sick, I looked pale, I had no muscle on me, there was no weight behind my punches. So, I think all that played a major role. … I felt fatigued from the medication and all that.”

Having surgery so close to their fight left Valenzuela unconfident in his conditioning, which the Renton, Washington resident feels kept him from capitalizing on his quick knockdown and stopping Colbert in the first round. Brooklyn’s Colbert was down during the seventh round of his previous fight, a lopsided points loss to Hector Luis Garcia, but he hasn’t been beaten by knockout or technical knockout in 18 professional fights.

“I think I had to just kinda pace myself,” Valenzuela said. “You know, I had to be smart. That juice, that extra push I was lacking was coming from [the surgery]. So, you know, it is what it is. Like, when I wanted to put my hands on him, I put my hands on him. You know, he’s not a hard fighter to hit. It was just all on my end that I had to like hold back a lot.”

Valenzuela parted ways with trainer Jose Benavidez Sr. after suffering a second straight defeat. He reconnected with his amateur trainer, Mario Rodriguez, who will work his corner during his rematch with Colbert at The Armory in Minneapolis.

To enhance his conditioning, Valenzuela trained at the Robert Garcia Boxing Academy in Riverside, California. He also did roadwork at a higher altitude on weekends during an eight-week training camp in Big Bear Lake, California.

“My conditioning is gonna be real good,” Valenzuela said, “and I don’t plan on getting tired.”

The rematch between Colbert and Valenzuela will be the co-feature of Showtime’s four-bout broadcast, the last “Showtime Championship Boxing” telecast of the premium cable network’s 37-run year in boxing. Cuban southpaw David Morrell Jr. (9-0, 8 KOs) will defend his WBA secondary super middleweight title against Ghana’s Sena Agbeko (28-2, 22 KOs) in the 12-round main event of a show scheduled to start at 9 p.m. ET.

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