That’s when the two ran into each other, just down the hall from where workers were assembling an eight-sided cage where they can beat each other’s brains and bend each other’s bones Saturday here at the Mandalay Bay Events Center.

Lesnar and Mir had spent the past few months taking shots at each other, each claiming he was the legitimate heavyweight champion and boasting about future domination.

Lesnar called Mir “a glorified Karate Kid.”

Mir mocked Lesnar’s Brazilian jiu-jitsu skills.

Lesnar, in a Spike TV interview, got so tired of watching a replay of Mir submitting him in their February 2008 fight, he stormed out and punched a door so hard it busted off its hinges.

Meanwhile, Mir moved on and decided to mock Lesnar’s coaches for not teaching the big guy basic defense.

“Yeah, I enjoy poking at the bear,” Mir laughed. “Keep poking at the bear.

“Maybe your opponent has a weak mind so maybe his coaches are keeping him away from you,” Mir continued, as subtle as a falling safe. “So maybe you screw with the coaches, maybe you say bad things about them, like they don’t know how to teach martial arts. Then they’re upset.”

Oh, Lesnar has screwed with Mir and Mir has screwed right back. It’s made for great sound bites, great television and mostly great hype leading up to this much-anticipated rematch.

There was Lesnar on Spike TV this week, claiming Mir benefitted in their first fight from a decision by referee Steve Mazzagatti. He half-jokingly accused them of sharing a hot tub together.

“I think [Mazzagatti’s] a cool guy, but I haven’t been in any hot tubs with him,” Mir laughed. He then noted that before the last fight, Mazzagatti had specifically warned against strikes to the head, which Lesnar was penalized for. So maybe Lesnar should’ve listened.

Undeterred, Lesnar claimed Mir grew up a nerd.

“That was a funny one,” Mir acknowledged. “I liked that one.”

“He had some good stuff,” Lesnar admitted. “I think mine were better.”

One of the reasons UFC president Dana White took a chance on Lesnar, a former champion in the scripted World Wrestling Entertainment, was that he could also bring a little bit of showmanship to the table.

Lesnar, 31, could sell a fight – in this case, the main event of a milestone card that is expected to produce a mixed martial arts record of more than 1.3 million pay-per-view buys.

“I worked for the circus,” Lesnar said of the WWE. “For me, [the back-and-forth insults] is a chance for me to let some personality out because I don’t do it a lot. I’m a private guy, but if I want to add a little salt and pepper on every once in awhile, that’s fine with me.”

The insults are not just showmanship, though. Lesnar is an undeniably intimidating dude, with little patience for anything.

Part of his mystique comes from his physique – a 6-foot-3, 265-pound mountain of a body. “I don’t exactly blend in with the crowd,” he joked.

The guy’s hands are so big, the UFC had to make him custom, triple XL-sized gloves. His shoulders look like they were cut from the trunk of a huge oak. His head is big and thick and sits sturdy on top of an oversized neck.

He lives deep in the Minnesota woods, where he lifts weights, drives around on tractors and emerges every so often to “get in a fight.” He abhors materialism and strives for simplicity. If it weren’t for hunting shows, he says he’d throw the family television out. If not a UFC star, he says he’d be a farmer.

He isn’t particularly jovial. On Wednesday, he was surrounded by lawyers and agents that take themselves way too seriously. He got shuffled about in a self-important manner that runs counter to the down-to-earth style of every other star in mixed martial arts. Everything around him seemed stressed.

Then to top it off, he’s liable to flash anger at any moment. He boasts that he has no respect for any opponent.

“I didn’t have any respect for Randy [Couture], I didn’t have any respect for Heath [Herring], I don’t have any respect for Frank,” he said. “There’s going to be a winner, there’s going to be a loser. As soon as you step in and have any respect for your opponent, I think you become the loser a hell of a lot sooner.”

No one knows what he’s going to do or if he can be contained. He’s the ultimate leading man for the UFC, with natural charisma to go along with his on-the-edge demeanor. Fans love him or hate him. They never ignore him. He knows that’s his role.

“There’s a lot of entertainment value to this stuff,” Lesnar said.

And that’s the complex side of him. He was in a pretty good mood Wednesday. He talked about how he’s “happy with my life.” He repeatedly spoke about his commitment to being a good husband and father.

He even laughed about the door he smashed off its hinges in his gym.

“You know, I just got done working out, I didn’t want to be there, I wanted to go home [and] eat,” he smiled. “I’m a sore loser. I don’t like to lose. To watch it over and over again was frustrating. I wanted the interview to be done. So I exited the building.”

He shrugged.

“It was just in the way and I was going through.”

He might as well laugh about it, because Mir already was. Perhaps Lesnar didn’t intimidate Couture or Hearing either, but he certainly won’t scare Mir. If part of Lesnar’s success comes from the psyche-out, he’ll have to win this one shorthanded.

Mir has reveled in giving it back to Lesnar, trying to turn the tables. And why not? He already survived two massive punches in the first fight, and while Mir certainly fell down, he notes that he was never so rattled that he stopped attempting submissions. Eventually he caught Lesnar in a knee bar. MMA is about mental strength, and that, he laughs, makes this a no contest.

Perhaps. Or perhaps he just hopes that idea gets inside Lesnar’s head.

If so, the first stare down of this contest was taking place at an unscheduled time and an unexpected place. The UFC had staggered the fighters’ interviews an hour apart to avoid just this type of meeting. There were no cameras around. Few people. This was real. The trash talk had been incessant and personal. You poke the bear and maybe the bear pokes back.

“Hey, Brock,” Mir said, extending a hand.

“Hey, Frank,” Lesnar said, shaking it.

They stopped, smiled and exchanged pleasantries. Mir’s wife, Jen, asked about Lesnar’s new baby boy. Lesnar returned the favor by asking about the Mirs’ 4-week old son. Jen produced a picture of the kids.

And just like that, so much for the animosity. The unsuspecting gym door was long forgotten. They’ll save the heat for the octagon on Saturday night.

Poke the Teddy Bear?

“That’s nice,” Lesnar said, looking gently at the Mir family picture he held in the huge hand that he plans on punching the patriarch of the clan with on Saturday. “That’s really nice.”