The move was first reported Tuesday night. Associate head coach J.B. Bickerstaff will be elevated to head coach.
"Over these last nine months, I have given my all to this organization, but after much reflection, I have decided that it is best that I step back and resign from my position as head coach of the Cleveland Cavaliers and assist the organization in a different capacity,” Beilein said in a statement. “I am very grateful to Dan Gilbert, Koby Altman and the entire Cavaliers organization for the opportunity they have provided me.
“This was a very difficult decision for me, but I want to be clear—this was my decision to step down and I truly appreciate the understanding and support of the front office during this time. I find losing very challenging and this year has taken a much bigger toll on me than I expected. I grew concerned for the consequences this toll could potentially take on my own health and my family’s well-being down the road. I was not certain I could be at my best for the remainder of the season and in the future. That would not be fair to the players, coaches and support staff.”
The team said Beilein will be assigned to a "different role within the organization."
The Cavaliers signed Beilein to a five-year deal in May 2019. Prior to joining the Cavaliers, he spent 12 years as head coach at Michigan, leaving with a 278–150 record and nine NCAA tournament appearances. He also previously coached at West Virginia, Richmond, Canisius, Division II Le Moyne and Nazareth College.
"I love the position the team is in to build and grow and this was something I felt was the perfect fit for me," Beilein said at the time of his hire in Cleveland. "With hard work and dedication by all of us, we will grow this team day by day and reinforce a culture of success that sustains itself with strong core values. Cleveland is a great city with amazing fans and I am really looking forward to calling Cleveland home for years to come.”
But Beilein, 67, has reportedly struggled with his transition to the NBA. The Cavaliers coach made headlines in January after mistakenly calling his players "a bunch of thugs" in a film session. His son Patrick Beilein’s resignation at Niagara in October has also taken a toll on him, per The Athletic.
Beilein is reportedly expected to say goodbye to his staff and players in the late afternoon on Wednesday, upon their return from the All-Star break
The Cavaliers hold a 14–40 record and are last in the Eastern Conference.
As a result of Beilein's departure, Bickerstaff is now taking over a team mid-season for the third time. Previously, he served as the interim head coach for the Rockets after the firing of Kevin McHale in 2015 and as the full-time head coach for the Grizzlies after they dismissed David Fizdale.
Bickerstaff has a career heading coaching record of 85–131 across three season. He was hired as Beilein's top assistant last summer.
The team's next game is on Friday, Feb. 21 against the Washington Wizards at 7 p.m. EST.