Arizona State University has placed head hockey coach Greg Powers on paid administrative leave as the school continues to examine an August workout that left defenseman Matthew Mayich hospitalized with devastating injuries. Mayich collapsed during an outdoor team workout on August 20 at Arizona State’s Tempe campus and has remained hospitalized since the incident.
The decision came after seven Arizona State hockey players sent a lengthy letter to university President Michael Crow challenging portions of the school’s previous review of the workout. The players asked for Powers and other members of the coaching staff to be placed on leave while an independent investigation is conducted. They said they were concerned about player safety and possible retaliation because the coaches still control playing time, scholarships and roster decisions.
Arizona State Athletic Director Graham Rossini said the university’s focus remains on Mayich, his family and the other players. Rossini said the school has continued gathering information and determined that placing Powers on leave was the best way to provide stability for the hockey program as the season begins.
Mayich, a 21-year-old defenseman who transferred to Arizona State from Clarkson University, suffered exertional heat stroke during the workout. His family’s attorneys have said he suffered severe brain damage and has an extremely poor prognosis. He was an NHL prospect whose rights are held by the St. Louis Blues.
Questions have centered on the conditions during the August 20 training session and how Mayich was treated after he began showing signs of distress. The workout was conducted outdoors and reportedly lasted more than 75 minutes. It was led in part by Tim Ziesel, a former Army Special Forces member who had been brought in to conduct the training session.
The seven players said in their letter that Mayich did not receive water during the workout. They disputed an earlier university review that described a water break occurring during the session. According to the players, only a small group reached the water before the workout continued, while Mayich and others did not receive any.
The players also said Mayich began showing signs of trouble well before he collapsed. They described him as disoriented and struggling during several exercises. At one point, according to their account, Mayich needed another player to help him remain upright. They said coaches and medical personnel did not adequately respond to those warning signs.
Mayich eventually collapsed during a medicine-ball relay. The players said he remained in direct sunlight for several minutes and was not immediately placed in a cold-water immersion tub, a method commonly used to rapidly cool athletes suffering from exertional heat stroke. They said towels, squirt bottles and water from a garden hose were used instead before emergency medical personnel arrived.
The players’ account differs in several ways from the university’s earlier review of the workout. They said the session lasted longer than the university initially reported and disputed descriptions of the weather conditions, water breaks and Mayich’s physical condition before he collapsed.
The players also said they were concerned that coaches involved in the workout remained in positions of authority while questions about the incident were still being investigated. Their letter was submitted through an attorney because they said they feared retaliation for speaking publicly about the incident.
Mayich’s parents have also called for coaches involved in the workout to be placed on leave. Their attorneys have argued that an independent investigation is necessary to determine what happened and whether university policies designed to protect athletes were followed.
The Arizona State Police Department is conducting a separate investigation into the incident. According to the Associated Press, the findings are expected to be reviewed by the Maricopa County Attorney’s Office. The police inquiry is separate from the university’s internal review.
The National Collegiate Hockey Conference, which includes Arizona State, said it supports the university’s decision to place Powers on leave while the circumstances surrounding Mayich’s collapse are examined. The conference said concerns raised by student-athletes should be heard and carefully reviewed.
Powers said he supports the university’s decision and wants the review to be independent and transparent. He has not publicly provided a detailed account of what happened during the workout.
Assistant coach Mike Corbett will lead the team as Arizona State opens its season against Lindenwood. The university said a separate interim head coach will be named soon. Corbett was also present during the August workout, according to reporting about the players’ letter.
Corbett has previously faced a legal issue unrelated to Mayich’s collapse. Court records reported by The Arizona Republic show that he pleaded guilty in December 2024 to a misdemeanor DUI charge. That case occurred well before the current controversy and was not an arrest connected to Powers being placed on leave.
Arizona State is now entering its season while dealing with questions about player safety, oversight and accountability. The seven players who came forward have asked university officials to ensure that athletes can participate in the investigation without worrying that their scholarships, playing time or roster positions could be affected.
The case has also brought attention to the risks of intense outdoor training in hot weather and the importance of rapid treatment for exertional heat stroke. Investigators are expected to examine the workout plan, hydration procedures, medical response and the roles of coaches and other staff members who were present.
For now, Powers remains on paid administrative leave while the investigations continue. Arizona State has not announced how long the leave will last or when a permanent decision about the coaching staff will be made.