(CBS-DETROIT) – Greg Harden, a renowned Mental coach for athletics at the University of Michigan who worked with thousands of student-athletes has died.

The university announced Harden’s death on Friday, saying he died of complications from surgery. Star athletes Harden worked with include Tom Brady, Desmond Howard and Michael Phelps.

The following is part of the statement the university’s athletic department released on social media:

“Longtime University of Michigan administrator Greg Harden, best known as a mental health coach to thousands of student-athletes who competed for the university and countless others around the world, has passed away following complications from surgery. During his time at Michigan, Harden became known in many circles as the school’s ‘secret weapon’ as he worked behind the scenes to help Wolverine athletes achieve peak performance.”

Several people affected by Harden have reacted to the announcement, including seven-time Super Bowl champion Tom Brady, who played football for Michigan from 1995 to 1999.

“I am so sad to hear the news of Greg’s passing. I am heartbroken as he was a dear friend and mentor. Greg had so many wonderful qualities that endeared him to so many people during his years at Michigan. He meant the world to me and I could never have had the success I did without the time, energy, love and support he gave me. He will truly be missed.”

JJ McCarthy, who played football at Michigan from 2021-2023 and is now quarterback for the Minnesota Vikings, issued the following statement:

“To OG, I cannot even describe the heartbreaking emotions I am experiencing right now. The intensity of this pain is only so immense because of the impact you have had on my life. You gave me the courage and faith as we stood hand in hand against the demons I have battled my entire life. You inspired me with your ability to love everyone and everything unconditionally. No matter how big or small, how significant or insignificant. You inspired me to seek the truth about who I really am, why I am the way I am, and to lift the veil of my limitless potential. You showed me what true freedom feels like when you helped me escape the cage in my head. But most importantly, you told me the things my ego didn’t want to hear. You always guided me to the places inside me I didn’t want to face. Your timeless wisdom, ever-present sense of humor, and genuine authenticity have left lasting impressions in so many hearts that we will carry with us for the rest of our lives. Especially mine. I wouldn’t be the person I am today without you, G. Thank you for everything. I love you, man. Sincerely, 9.”

Desmond Howard, who spent 11 seasons in the NFL, played college football for Michigan and works as an ESPN College GameDay analyst, issued the following statement:

“Although my family and I are heartbroken, we hold on to the lessons, guidance and memories that will forever be Greg’s legacy. We are blessed beyond measure to have had him in our lives.”

Harden worked for the athletic department for 24 years. He retired from his full-time position in 2019, but continued to work as a consultant to the athletic department until his death.

Coaches and athletic administrators at the university relied on Harden’s expertise to adequately address the needs of student-athletes.

He was featured on an episode of “60 Minutes Sports,” where he was called “Michigan’s secret weapon” for his impact as a mental coach for student-athletes, according to the university’s website.

Harden leaves behind his wife, sister and three adult children.

“The family is grateful for all the thoughts and prayers, but asks that they be given some privacy as they cope with the loss of their loved one,” Michigan Athletics said in a statement. “In the future, they look forward to celebrating Greg’s life with many who were fortunate to know him.”