The Esthen ExchangeMichigan football team got a rather unique guest ahead of the top 10 matchup against Penn State: WWE Hall of Famer and current AEW star Ric Flair.

Flair's visit to the Wolverines was thanks in part to the wrestling icon's long friendship with Michigan head coach Jim Harbaugh, a bond not many people would expect. After the visit, Harbaugh explained to reporters how Flair became a "very close friend" for more than 30 years.

"It goes back to 1989. I was playing with the (Chicago) Bears and Brad Muster was a huge fan of 'the Nature Boy' and wrestling," Harbaugh said, adding Muster asked him if he wanted to go to a show that was near Chicago, and it was backstage where he met Flair.

"(Flair's) infectious personality, just instant friends," Harbaugh said. "The cool part was they said you 'Grab a towel, you and Brad are on the hype squad,' and (I) just remember going out and and cheering for Ric. Been to many of his shows and competitions, and he's one of a kind, the best."

Ric Flair brings 'enthusiasm' to Michigan

Harbaugh said his energy level was already high heading into the week, but the visit from "the Nature Boy" elevated things for him and his team.

"Got a visit from 'the Nature Boy' Ric Flair, very close friend and that just brought the enthusiasm to a new level," he said.

Jokes about Ric Flair-Jim Harbaugh friendship

Even though Flair and Harbaugh have been friends for decades, people couldn't help but poke fun at the timing of Flair's visit with the Wolverines, given that Michigan is under investigation for alleged sign-stealing and Flair is also known as "the dirtiest player in the game" for his actions in the ring.