Arizona State University hockey player Matthew Mayich is in a coma in hospital after collapsing during an extreme outdoor workout in Phoenix last Thursday morning.
The 21-year-old sophomore defenseman remains in critical condition as doctors treat what is being investigated as a possible cardiac event following the high-intensity session.
Prayers and support have poured in for Mayich across Arizona and from his hometown in Ontario, Canada, while university officials review the circumstances surrounding the incident.
The outdoor training session lasted approximately one hour and was described as "both atypical and extreme," according to a report by The Athletic.
The workout was led by Tim Ziesel, a former U.S. Army Special Forces service member and Green Beret who is not employed by the university. Ziesel, who was initially identified by The Arizona Republic, declined to comment on the specifics of the training, stating that he "didn't know the whole situation."
Extreme heat and grueling drills
The session took place at Sun Angel Stadium, an outdoor track and field facility located on the Arizona State campus at 400 S. Rural Road in Tempe. Phoenix was under an extreme heat warning at the time, with an average daily temperature of 92.5 degrees Fahrenheit and an afternoon high reaching 106 degrees.
Emergency responders from Tempe Fire Medical Rescue were called to the stadium at approximately 8:31 a.m. following reports of a heat-related illness. Medical crews treated Mayich at the scene before transporting him to a local hospital.
According to details published by The Athletic, players were put through a grueling routine consisting of sprints, planks, push-ups and bear crawls. The instructor placed heavy emphasis on athletes repeating instructions back to him and keeping correct count of each exercise repetition.
Players were allegedly forced to complete extra sprints or exercises if they failed either task or lagged behind other groups. Reports from The Athletic indicate that athletes were also told not to complain during the session.
The final activity involved running the length of a football field and back while carrying a medicine ball. The instructor is said to have left before that final section was completed.
University investigation and NCAA rules
Arizona State University, a Phoenix-based institution whose Sun Devils hockey team competes in NCAA Division I, confirmed earlier this week that it has launched an investigation into the incident.
Chris Fiscus, Vice President of ASU media relations, confirmed that a student-athlete from the hockey team remains hospitalized following the Thursday morning workout.
"A student-athlete who collapsed during an outdoor exercise Thursday morning remains hospitalized," Fiscus said. "The student-athlete, a member of the ASU hockey team, is not being named by the university because of privacy interests. The university is reviewing the circumstances surrounding the workout."
Under National Collegiate Athletic Association rules, college hockey teams are permitted to start formal activities as soon as classes begin. Arizona State started its fall semester last Thursday.
NCAA heat safety guidelines note that student-athletes who are new to a program and climate could be particularly at risk of heat illness. Mayich was one of 18 new players to join the Sun Devils team this offseason.
Family response and hockey career
Mayich transferred to Arizona State in March following a strong season at Clarkson University, a private university in Potsdam, New York. Playing for the Clarkson Golden Knights during the 2025-26 season, the defenseman recorded 15 points on seven goals and eight assists.
Before playing college hockey, Mayich spent four years in major junior hockey with the Ottawa 67s of the Ontario Hockey League, where he served as an assistant captain.
Mayich was selected by the St. Louis Blues in the sixth round of the 2023 National Hockey League Draft. He attended two prospect development camps with the Blues in 2023 and 2024, but never signed an entry-level contract.
Speaking to The Arizona Republic, Mayich's cousin, Victoria Beara, reflected on the community response. "Even though we are going through this heartbreak, it is truly such a blessing to see everyone praying and just the impact Matthew has had on so many people," Beara said.
Tributes from former teams
Statements of support have been issued by organizations across North American hockey following news of Mayich's condition.
The St. Louis Blues released a formal statement offering prayers for his recovery. "The entire Blues organization is keeping Matthew Mayich close to our hearts as we pray for his comfort and recovery while he continues to undergo medical treatment in Arizona," the team said. "His agent has kept us informed about Matthew's medical status over the last week, and we extend our deepest support to his family, friends and teammates during this difficult time."
The Ottawa 67s also issued a release supporting their former assistant captain. "The Ottawa 67's are aware of the hospitalization of our former assistant captain, Matthew Mayich, and are keeping him and his family in our thoughts during this incredibly difficult time," the organization said. "Out of respect for Matthew and his family's privacy, the organization will not provide further comment at this time."
