The first defeat stings differently when you’re unbeaten. Adrian Lee tasted that bitter reality in September and returns hungry to prove it was temporary.

Lee faces Shozo Isojima in a lightweight MMA bout at ONE Fight Night 40 on Friday, February 13, inside Lumpinee Stadium in Bangkok, Thailand.

The 19-year-old Hawaiian started his professional career perfectly. He submitted Antonio Mammarella in his promotional debut at ONE 167 in June 2024. Nico Cornejo followed via first-round rear-naked choke at ONE 168. Takeharu Ogawa lasted just 63 seconds at ONE 172 before succumbing to an anaconda choke. Three fights. Three first-round finishes. Three $50,000 performance bonuses.

Then Tye Ruotolo happened. The ONE Welterweight Submission Grappling World Champion made his MMA debut last September against Lee. The Californian showcased budding striking and elite grappling credentials. Ruotolo forced Lee to tap via rear-naked choke in the second round. The experience taught lessons no training camp replicates.

Isojima knows exactly how that feels. The 28-year-old Japanese fighter fell to Ruotolo via rear-naked choke at ONE 173 in November. Both men suffered their first career defeats to the same elite grappler. That shared experience creates a fascinating matchup between fighters desperate to bounce back. The 6-1 Kuwana native carries credentials but faces similar demons.

“That fight with Tye, it was a rough one,” he said. “When I was in that ring with Tye, it was kind of new. Tye was definitely the highest caliber opponent I’ve fought so far, and I think it was definitely a little bit of a shocker. I didn’t think that he’d get under me so fast and that he’d get right into the takedown. I went right into his world. It kind of just started off on a bad foot and kept going his way throughout that fight. So, there was definitely a lot to learn.”

Adrian Lee extracted valuable lessons from his setback

The 19-year-old Prodigy Training Center product analyzed his performance objectively rather than making excuses. He rested his body for weeks after the loss. Then he returned to training with new fire. The gaps in his game needed fixing. Composure under adversity required development.

That mental adjustment matters most. Lee had never been taken down before Ruotolo. He’d never lost positions in previous fights. The unfamiliar territory made everything feel worse than reality. His head told him he was losing worse than he actually was. Experience came at a price.

“The biggest lesson I learned from that fight was my composure,” he said. “It was the first time I’ve ever been put in a position like that in any of my fights. In my head, I had thought I was losing the fight a lot worse than I was just because I’ve never gotten taken down. I’ve never lost any positions in a fight before. So definitely, it added a lot to my experience. Now, I know how to stay more composed and more level-headed during a fight. I’m excited to show that in this next fight.”

Isojima represents the perfect opponent for Lee’s return. The Japanese fighter brings resiliency and grinding ability. He can strike, take opponents down, and hold them down with ground-and-pound pressure. His judo and wrestling accolades provide legitimate credentials.

But Lee sees weaknesses. Isojima gets touched up frequently in his fights. The Hawaiian believes he’ll dominate everywhere the fight goes. His training since childhood created a fighter who flows between striking, wrestling, and grappling seamlessly. That versatility represents his biggest strength.

“I think his biggest strengths are probably his resiliency and his ability to just grind,” he said. “He’s a grinder. He’s able to strike, take you down, hold you down, and ground-and-pound. And then for weaknesses, I’ve seen him get touched up a lot in his fights. He has some accolades in his judo and his wrestling, but I believe that I’ll beat him everywhere in this game.”