John Beilein’s NBA tenure didn’t even last a full season.

The winningest basketball coach in Michigan history has resigned as the Cleveland Cavaliers’ head coach, according to a report.

ESPN NBA insider Adrian Wojnarowski reported on Tuesday night that Beilein is leaving his position and was “expected to say goodbye to staff and players on Wednesday upon (the) team’s return from (the) All-Star break.”

It was Beilein's first season in the league after spending the previous 41 seasons at the college level, the last 12 at Michigan. Cleveland is 14-40, the worst record in the Eastern Conference. That's as many losses as Beilein had suffered over the past four seasons combined.

There were other issues that popped up this season, including one completely out of Beilein's control. His son Patrick stepped down from his first Division I head coaching job, at Niagara, before the season began, citing personal reasons.

There were reports of Cavs players being unhappy with Beilein's style, which included a focus on fundamentals and film study. In January, Beilein apologized after mistakenly calling the players "thugs" during a film session.

"When people would say to me, 'You're going to lose more games in one season than you've lost in the last three or four combined,' I didn't get my head around that," Beilein said in January, when the Cavs were in Detroit.

"It is frustrating walking into a locker room after a game and basically saying the same thing: We're growing, we're going to get better, we got to get back to work tomorrow and find the answers."

Beilein, who turned 67 earlier this month, had signed a four-year deal with a fifth-year team option, reportedly worth at least $4 million annually, after leaving Michigan abruptly in May. Michigan replaced him with Juwan Howard.

The Cavs last played on Feb. 12, beating the Hawks, before pausing for the All-Star break. They play again on Thursday. Former associate head coach J.B. Bickerstaff will take over as head coach, according to Wojnarowski.

Beilein began his career as a junior varsity high school coach and hit every rung on the coaching ladder: junior college, Division III, Division II, and four different Division I gigs. He was a head coach throughout.

Michigan hired him from West Virginia in 2007. He ended the program's 10-year NCAA Tournament drought in his second season, then made deep runs the expectation. Over his last seven seasons, the Wolverines reached at least the Sweet 16 five times. That included two appearances in the national championship game. Beilein compiled a record of 278-150 in Ann Arbor.

"When the opportunity came when you could do even more pure coaching, I thought long and hard about it," Beilein said in May about the Cavs' job. "It was the right decision." He noted Cleveland's proximity to Ann Arbor was appealing as well.

Many inside the college game wondered whether Michigan losing so many players early to the NBA, in addition to the FBI probe revealing dirty recruiting tactics at other top programs, encouraged Beilein's decision to leave.

Regardless, his time in the NBA was as brief as it was disappointing. Cleveland had three losses of at least 40 points this season.

In October, during the NBA preseason, Beilein returned to the state of Michigan to coach for the first time since leaving the Wolverines. He talked about not having to worry about recruiting or academics.

"It is not a tougher grind than being a college coach," Beilein said. "It's a different grind. It's a basketball grind and I love it."

That love, at least for now, is gone.