The Jim Harbaugh era with the Michigan football team was a success as the Wolverines are the defending national champions. They have won three straight Big Ten titles, they have beaten Ohio State three times in a row and they have gone to the College Football Playoff three years in a row. Michigan reached the peak with its national championship, but after that, Harbaugh left for the NFL.

Jim Harbaugh was an NFL coach before he came to Michigan football as he was the head coach of the San Francisco 49ers. Now, he is back in the pros as the head coach of the Los Angeles Chargers.

It wasn't a surprise that Harbaugh left for the NFL. He had entertained NFL jobs before, and while he achieved his goal of winning a national title, he hasn't won a Super Bowl yet. Still, Michigan fans were obviously sad to see him go. He left the Wolverines in a great spot, and it is Sherrone Moore's job to keep them there.

An excerpt from a new book, The Price: What It Takes to Win in College Football's Era of Chaos, which comes out in August, revealed some new details about Harbaugh's departure. According to the book, Harbaugh did want to stay at Michigan, but athletic director Warde Manuel seemed to impact his decision to leave.

“During a two-day getaway with his wife Sarah on Coronado Island off the coast of San Diego, Harbaugh unloaded to longtime friend Todd Anson,” The book read. “He told Anson he wanted to remain at Michigan but believed [Warde] Manuel—no matter his public pronouncements—was not the advocate he needed in his corner, particularly in front of the Board of Regents. He also raged against Big Ten commissioner Tony Petitti, who before the three-game Big Ten suspension had promised to meet Harbaugh in Ann Arbor and brief him on what the conference was doing, only to stand him up. [Through a spokesperson, Petitti declined an interview request.]

“The day after his outburst to Anson, Harbaugh had an initial interview with the Los Angeles Chargers. Afterward, his tone had softened. Leaning toward taking the NFL job, if offered, he dialed down the Manuel rhetoric, no longer interested in a potential legal battle and fighting people he later said were ‘gunning for me.' It suggested in attitude and tone that his days in Ann Arbor were numbered.”

It's no secret that Michigan fans don't love Warde Manuel, and this isn't going to help change that.

Warde Manuel says that he put a lot of effort into keeping Jim Harbaugh on board

U-M athletic director Warde Manuel speaks during introductory press conference for Dusty May at Junge Family Champions Center

In the time between Michigan football winning the national title and Jim Harbaugh leaving for the Chargers, Warde Manuel said publicly numerous times that he is working on getting a new contract for Harbaugh. He has heard the negative things said about him, but he insists that he put in a lot effort to keep Harbaugh around.

“I hear about what was happening on social media, some of the language and things that people directed my way,” Manuel said. “That doesn't take away from the effort we put into it. They have no idea what communication and conversations we had.”

At the end of the day, whatever effort put in wasn't enough. Harbaugh is gone. The Sherrone Moore era is now underway in Ann Arbor.