"Let me tell you something, I'll tell you this and I've never said this before ever in an interview anywhere, and if Vince hears this, he's going to go nuts, okay? Vince is too old, which he won't think he is and he'll go crazy, and he wanted to do that one time. Vince wanted to fight me, I swear to god. He called me up and said, 'let's do it. We can either do it in the UFC or let's do it at WrestleMania.' And I said, 'You are crazy, man.' Vince is... a lot of people talk about Vince, I always have said it and I'll say it again: I respect Vince very much but Vince is too old to be fighting."
Now Dave Meltzer of MMA Fighting has revealed the back story behind the out-of-left-field challenge:
The suggestion by McMahon was actually made on or around Oct. 15, 2010, actually stemming from what at the time McMahon was looking for as his main event for WrestleMania 27, which took place on April 3, 2011 at the Georgia Dome in Atlanta. It ended up drawing 61,617 fans. McMahon, who had used Mike Tyson, Muhammad Ali, Lawrence Taylor and Floyd Mayweather Jr., on WrestleManias in the past, was looking to match up then-UFC heavyweight champion Brock Lesnar, with The Undertaker, as the main event.
White nixed the idea for the obvious business logic of not wanting his champion doing pro wrestling at the same time they are trying to promote his real fights. ... But McMahon thought himself against White could also be a headline event on the show.
The idea was for a pro wrestling match, but McMahon, a bodybuilder who was 65 at the time, actually said if White felt it wasn't the right thing for him to do a staged fight, they could still do the match - for real.
"I laughed and said, 'You're crazy, you're out of your mind,' White said when the subject was brought up a second time after UFC 158 by Ariel Helwani on Fuel TV. "In the interview (the night before), I said Vince was too old. We're both too old. I'm too old, too, just for the record.
In the end McMahon managed to talk Dwayne "The Rock" Johnson into main eventing WrestleMania.
Ah the combat sports/sports entertainment world, it's cray cray.