A former Green Beret who now volunteers with the Arizona State University hockey program led an outdoor training session on a recent Saturday, according to teammates and witnesses.
During the workout, first‑year forward Matthew Mayich, a 19‑year‑old from Stoney Creek, Ontario, collapsed suddenly and was immediately taken to a local hospital.
Mayich was diagnosed with a cardiac event and is currently being treated at the Barrow Neurological Institute, where he remains in a coma, family members confirmed.
Tim Ziesel, the ex‑Special Forces captain who organized the session, left the field before the collapse occurred, though he later said the workout was described as moderate and included water breaks and compliance with NCAA guidelines.
University Response and Review
ASU officials have declined to disclose specifics but announced a thorough review of the incident, stating that player safety is a top priority for the university’s athletics department.
The episode has drawn prayers and commentary from the campus community, with several deacons from local churches offering support and calling for transparency as the investigation proceeds.
Ziesel’s own background includes a 2023 motorcycle accident, participation in faith‑based training at Arizona Christian University, and a history of leading similar conditioning drills for the team in 2025.
Mayich, drafted by the St. Louis Blues in the 2023 NHL Draft, was part of the 2026 transfer portal class and had been hoping to contribute to the Sun Devils’ roster this season.
While the university has not released a timeline for the review, the incident underscores the risks inherent in high‑intensity training and the importance of medical oversight.