Former Michigan football coach Jim Harbaugh has maintained his departure for the NFL was simply a business decision and he has nothing but love for his alma mater.

But that doesn't change that, intentionally or unintentionally, last season's defensive coaching staff has been wiped out for his successor, and mentee, Sherrone Moore.

Not only did Harbaugh leave to take over the Los Angeles Chargers, but he took with him defensive coordinator Jesse Minter, head strength & conditioning coach Ben Herbert, defensive line coach Mike Elston and defensive backs coach Steve Clinkscale, all of whom will hold the same positions in L.A.

Interim linebackers coach Rick Minter, father of Jesse and a longtime college head coach, also left to follow his son out West as a senior defensive analyst. Also, Dylan Roney, a former graduate assistant who worked alongside Elston was announced as a defensive analyst by the Chargers on Wednesday.

Harbaugh also tried to bring his son Jay as special teams coordinator, but Jay decided to take the same position with the Seattle Seahawks.

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Despite the lengthy list of departures, athletic director Warde Manuel didn't express any animus about the offseason turnover of the reigning national champion football team's staff, but rather optimism about the chances it creates.

"I knew it was a possibility that Jim would want to talk to some staff about going there,” Manuel said. “As I had with Jim, I never got mad at people having an opportunity and making a decision. Some had already been talked to before Jim was selected as head coach of the Chargers.

"These are decisions people make and it happens over time and it gives Sherrone an opportunity to rebuild the staff, particularly on the defensive side, in the way that he wants, and I feel good about the people that he’s bringing on.”

Manuel was also asked Wednesday if there would be more funds allocated for assistants to try and entice higher-profile coaches to join the staff, considering Moore's $6 million salary is about half of what Harbaugh was reportedly offered by U-M to stay.

Not only has the assistant salary pool grown, Manuel said, but he expanded it when he was still trying to keep Harbaugh.

“Prior to Jim leaving, I invested more in our assistant pool, really brought it up by a couple million dollars,” Manuel said. “That remains with Sherrone, in terms of that investment.

“I won't go into details but all of those discussions (to try and keep coaches) have occurred and so it doesn't matter what we've done, people made choices to leave. I will tell you it wasn't because of a lack of effort on our part to keep people here.”

Michigan reportedly brought on Don "Wink" Martindale more than a week ago as defensive coordinator, but has yet to make the hire official.

No update on NCAA Investigations

The Michigan football program remains under multiple NCAA investigations, something Manuel doesn't expect to change even as Harbaugh has moved on to NFL.

Manuel said he has not heard specifically from the NCAA about it.

“Their investigation is ongoing,” he said. “I don’t think (Harbaugh leaving) will change any of the investigation into the matter. It will continue to move forward, and we’ll see where it goes from there. We will continue to work with them, we will continue to support their efforts to investigate this and deal with the different aspects of it as it comes up.”

U-M received a notice of allegations in December regarding a series of Level II allegations, among them analysts serving in on-field coaching capacities, coaches overseeing players' workouts via Zoom and contact with recruits during a COVID-19 dead period.

Harbaugh was also tagged with a Level I violation after he was asked about the matter by NCAA investigators and claimed he did not know; the NCAA deemed him to be misleading its officials.

Michigan suspended Harbaugh for three games after he and the NCAA failed to reach a negotiated resolution. Moore was also suspended for the first game, as was now-offensive line coach Grant Newsome.

U-M is also under investigation for a sign-stealing scheme, reportedly orchestrated by the now-former staffer Connor Stalions. Harbaugh proclaimed his innocence in a statement shortly after news of the investigation broke in October and remains adamant he did not have any knowledge of the plot.

Harbaugh served a Big Ten-imposed three-game suspension to end the regular season.

Contact Tony Garcia: apgarcia@freepress.com. Follow him at @realtonygarcia.

This article originally appeared on Detroit Free Press: Michigan AD on football staff turnover: 'I knew it was a possibility'