Diego “Cut-Throat” Cortez is a rising star in Muay Thai, a fast-paced, full-contact sport known as the “art of eight limbs.” Using both fists, shins, elbows and feet, Cortez has compiled a record of 15-0 with eight knockouts.

Curiously, his toughest fight wasn’t the one that left him with a fractured right hand. It wasn’t the one that split open an eyebrow. And it probably won’t be the one on Feb. 1 against a nine-time champion for the WBC Muay Thai National Amateur Middleweight title.

No, the most difficult fight for Cortez, 21, was the one he chose three years ago. After graduating from high school with a 3.9 grade point average, Cortez declined a scholarship offer from the University of Kansas to pursue a career in martial arts. 

Diego Cortez offers strength and conditioning classes through his training business, Havoc Athletics. He operates out a gym he outfitted in his friend’s home garage.
Diego Cortez offers strength and conditioning classes through his training business, Havoc Athletics. He operates the gym out of his friend Alec Falgout’s garage. Credit: Bria Woods / San Antonio Report

Full-time athlete

With money saved from waiting tables and catering, Cortez drove from Indio, California to San Antonio, where he grew up. He rented a room from a friend, worked three jobs to support himself and saved what he could to start his own business. Despite little sleep and much exhaustion, he also made time to work on Muay Thai. “That was rough,” Cortez said.

Fresh out of high school, he logged more than 60 hours a week as a stretch practitioner, strength and conditioning trainer and driver for UberEats. When Cortez wasn’t working, he was training, seven days a week.

Two years after leaving California, Cortez had saved enough to outfit his friend’s garage with equipment and start a training business, Havoc Athletics. His website includes testimonials from satisfied clients.

“Diego just completely made it to where he can be a full-time athlete,” said Bobby Peek, Cortez’s coach. “I’ve never seen anything like his level of dedication. On his 21st birthday, he did not go out and get a drink. He was in the gym working. That’s how he celebrated.”

Diego Cortez eats a third meal around 1pm. While training for the WBC Championship on Feb 1, Cortez is consuming around 2,700 a day.
Diego Cortez eats a third meal around 1 p.m. on Wednesday. While training, Cortez consumes around 2,700 calories a day. Credit: Bria Woods / San Antonio Report

Cortez is preparing for Chase Brooks (22-5), his opponent for the WBC middleweight title in Largo, Florida. A native of Tampa, Brooks has won nine Muay Thai championships at 160 pounds. Win or lose, Cortez will represent Team USA at the Pan-American Championships Feb. 13-16 in Monterrey, Mexico. “I’m honored,” Cortez said, “and very excited to represent my country.” 

‘The hardest work I’ve ever had’

Cortez came to martial arts at the behest of his parents, who wanted him to learn self-defense. A 13-year-old football player at Smithson Valley Middle School, Cortez was large for his age and insecure about his body. “I wanted to lose weight,” he said.

He found a Muay Thai video online and discovered a gym near his home in Comal County. Peek agreed to train him. Initially, Cortez did not impress.

“He came to me as a chubbier kid,” recalled Peek, head coach of the San Antonio branch of Ambush Muay Thai. “His movement was really awkward. I didn’t see anything in him at the time, to be honest, as far as being a competitive athlete. But that changed.”

Bobby Peek (left) first started coaching Diego Cortez in May Thai when Cortez was still in middle school.
Bobby Peek (left) first started coaching Diego Cortez in Muay Thai when Cortez was still in middle school. Peek has been instrumental in bringing Muay Thai to Texas and he is the Texas state representative for WBC Muay Thai USA. Credit: Bria Woods / San Antonio Report

Cortez began waking up at 5 a.m. to lift weights. He turned fat into muscle and worked ferociously in the gym. “I thought he would burn out, he was going so hard,” Peek said. “But he kept that pace. He’s the hardest worker I’ve ever had, and we’ve had a guy who was ranked No. 1 in the nation as a pro.”

Peek is referring to Peter Stanonik, who won the WBC Muay Thai USA middleweight professional championship in May. 

As Cortez’s skill and promise accelerated, a bombshell dropped. The young fighter’s  mother and father decided to move to California to help their parents. Although Cortez promised to return after high school, Peek did not see that happening. Cortez would be near the beach. He’d make new friends. “I thought I’d never see him again,” Peek said.

Diego Cortez (right) trains with Sam Williams at Ambush Muay Thai Wednesday. With a 15-0 record including eight knockouts, the 21-year-old will travel to Florida on Feb. 1 to compete for the for the WBC Muay Thai National Amateur Middleweight title.
Diego Cortez (right) trains with Sam Williams at Ambush Muay Thai. With a 15-0 record, including eight knockouts, the 21-year-old will travel to Florida on Feb. 1 to compete for the WBC Muay Thai National Amateur Middleweight title. Credit: Bria Woods / San Antonio Report

A world of opportunities

After wrestling for two years at La Quinta High School, Cortez returned and resumed training with Peek. The kid tore through every opponent, knocking out most with knee strikes to the liver. In June, he won a Thai Boxing Association national tournament in Ardmore, Oklahoma. “He’s only had one tough fight,” Peek said. “Outside of that one, he’s steamrolled everybody.”

The coach understands Cortez’s potential as well as anyone. Peek is a former Muay Thai national amateur champion at 155 pounds. He’s also a Muay Thai matchmaker and promoter, a commentator at major fights. He predicts Cortez will turn professional with the goal of competing in the UFC (United Fighting Championship). 

Diego Cortez, 21, is preparing for the WBC middleweight title in Largo, Florida on Feb. 1. Cortez will also represent Team USA at the Pan-American Championships Feb. 13-16 in Mexico City.
Diego Cortez will represent Team USA at the Pan-American Championships Feb. 13-16 in Monterrey, Mexico. Credit: Bria Woods / San Antonio Report

“With his work ethic,” Peek said. “I can’t rule anything out. He can go as far as he wants to go.”

Cortez envisions a world of opportunities, either in the U.S. or in Thailand, the birthplace of Muay Thai. After his WBC middleweight title fight in February, Cortez will decide whether to continue in Muay Thai or transition to mixed martial arts (MMA). Whatever the case, he aspires to become a world champion. 

“Ever since I started fighting,” he said, “I feel like I found what I was meant to do.” 

This article has been updated to reflect the correct location of the Pan-American Championships, which will take place in Monterrey, Mexico.

Ken Rodriguez is a features writer for the San Antonio Report's Live Like a Local section, focused on San Antonio's culinary scene. He is a San Antonio native and award-winning journalist.