Arizona State head coach Greg Powers has been placed on paid administrative leave amid an investigation into the circumstances surrounding a medical emergency during a military-style workout that left one player in a coma.
Sun Devils hockey star Matthew Mayich has remained in that coma since collapsing during the outdoor training session in late August due to heat stroke. After he was hospitalized, The Athletic reported the Sun Devils’ outdoor workout lasted around an hour and was considered ‘both atypical and extreme’ amid rising temperatures in the Phoenix/Tempe area – reportedly in the mid-to-high 80s.
Arizona State University Police have launched an investigation into the incident.
The school released its own initial report earlier this week, but did not blame any party for the intense military-style workouts that preceded the 21-year-old’s collapse and subsequent coma. He is not expected to make a full recovery, according to his family’s attorney.
Since then, seven Sun Devils hockey players sent a letter to the school president calling for the coaching staff to be placed on administrative leave while disputing some of the supposed facts included in ASU’s initial probe.
Now the school has taken action by sidelining Powers and placing assistant Mike Corbett in charge for Friday’s season opener in Missouri.
Arizona State head coach Greg Powers has been placed on administrative leave amid an investigation into the circumstances surrounding last month’s medical emergency

Arizona State has released its initial report on the hospitalization of Matthew Mayich
The National Collegiate Hockey Conference (NCHC) has issued a statement of support for the decision.
‘The concerns raised by student-athletes deserve to be heard and thoroughly reviewed,’ read the statement. ‘We will not prejudge the findings of that review. Hockey matters deeply to our conference, but the well-being of our student-athletes matters more.’
The players who penned the letter did so anonymously out of fear of retaliation, according to The Athletic, which first revealed the existence of the message.
‘We are submitting this report anonymously because we fear retaliation from the coaching staff,’ the letter read. ‘That fear is not directed at one person. The head coach and his assistant coaches were all on the field on August 20, all remain in their positions, and together they decide our playing time, scholarship levels, and roster status. No one has separated us from them since that morning.’
Mayich’s parents John and Christina have also released a statement through their attorney, echoing some of the comments made by their son’s teammates.
‘We’ve heard some things about what our family wants that aren’t right, so we want to be clear: we want this team to have a great season and we’ll be cheering for you,’ the Mayichs wrote in an open letter shared by attorney Rob Carey. ‘But the coaches who ran that workout on August 20 need to be removed while an independent investigation gets to the truth. The players shouldn’t have to worry about retaliation from the people they report to every day.’
An Ontario native who was drafted by the St. Louis Blues in 2023, Mayich suffered exertional heat stroke that led to a lack of oxygen to his brain prior to his collapse. Carey has blamed the military-style workouts arranged by a former US special forces service member.

Powers (right) previously blamed the Sun Devils’ struggles on being too ‘soft’
The review and timeline released Tuesday reported that the team’s coaching staff did request permission for an ex-Green Beret, Tim Ziesel, to speak with players, but added they did not submit Ziesel’s training activities to strength and conditioning coaches for review.
Ziesel did not have a contract for the three-day ‘team-building’ exercise described in the timeline, and he had left the campus before Mayich collapsed.
The former US special forces service member is a non-university employee and has declined to talk about the workout, saying he ‘didn’t know the whole situation.’
Players reportedly were put through their paces in a grueling session consisting of sprints, planks, push-ups and bear crawls. There was an emphasis on repeating instructions back to the instructor and keeping correct count of each exercise.
The Sun Devils were allegedly forced to complete extra sprints or exercises if they failed either task or lagged behind other groups. It is claimed by The Athletic they were also told not to complain.
The final activity was a run with a medicine ball the length of a football field and back, but the instructor is said to have left before that section was completed.

Arizona State’s hockey team is 11 years old and features players from across North America
Like the other participants, Mayich did pass a physical exam that cleared him to participate in the team workouts.
Much has been made about the atmosphere surrounding the Sun Devils hockey program. Powers previously attributed the team’s struggles last season to being too ‘soft,’ as he told 247Sports in May.
Months earlier, Powers was introduced to Ziesel through Arizona State hockey supporter James ‘Winky’ Fairorth, which led to the team-building exercises last month, according to The Athletic.
A day before the workouts, Powers told players they were embarking on a ‘team building exercise with physical activity built in’ and urged the student athletes to ‘hydrate and eat well.’
Although the timeline reports that Powers told Ziesel to do a water break 20 minutes into the workout, it’s unclear which players actually got to take a drink. Sources told The Athletic that those who were late finishing exercises were asked to perform extra reps, preventing them from hydrating.

Mayich, a Canadian player, transferred to Arizona State after suiting up at Clarkson
‘I know that water break didn’t include the people who were late in the exercise, which are the people that need it the most,’ Carey said.
Mayich did appear disoriented during the workout, according to the review timeline, which claimed he stumbled and fell while holding a medicine ball. Tempe Fire Medical Rescue was called shortly after the workout ended to deal with a ‘serious heat emergency’ as a trainer applied iced towels and cool water.
Although Arizona State University Police are investigating the incident, Carey has called for the school’s officers to give the case to Phoenix PD.
‘I have very little confidence that ASU is trying to get to the truth here,’ Carey told The Athletic. ‘If they were, they’d be talking about who made the mistakes here and why the mistakes were made and what’s going to be done to correct that or prevent that in the future.’

