DOJO – The Chicago fight community is mourning the death of 31-year-old MMA and Muay Thai fighter Isaac Johnson, who collapsed during a match on Friday night at the Matador Fighter Challenge in Cicero, Illinois.

Johnson was competing in a heavyweight Thai boxing fight when he went down late in the third round. Emergency medical staff responded at 8:38 p.m. and transported him to Loyola University Medical Center, where he was pronounced dead at 12:01 a.m., according to officials.

What happened during the fight?

Witnesses say Johnson collapsed toward the end of his bout against fighter Mario Aleksandrovski. This was Johnson’s first Muay Thai match, despite previous MMA experience.

The Matador Fighter Challenge promoted the night as a high-intensity combat event featuring “local warriors” in MMA and Thai boxing matchups.

Promoter Joe Goytia confirmed Johnson had passed all required state physical exams before stepping into the ring.
“I don’t have the words to express how I feel right now,” he wrote on Facebook. “Medical staff treated him immediately… I was informed around 1:30 a.m. that he didn’t make it. My deepest condolences to his family, friends, and teammates.”

What investigators are looking into

The Cook County Medical Examiner’s Office has scheduled an autopsy to determine the cause and manner of death.
Meanwhile, the Illinois Department of Financial and Professional Regulation (IDFPR) — the agency that oversees combat sports and licensing — announced it is reviewing the circumstances surrounding Johnson’s passing.

Local police in Cicero have also launched a death investigation.

Community reaction

Johnson trained at Chicago’s Mission MMA & Fitness, where members described him as “an incredible person, a great friend and loving father.” The gym asked the public to respect his family’s privacy as they grieve.

Johnson leaves behind teammates, loved ones, and fans shocked by the sudden loss.