Brock Lesnar thinks he has come a long way as a fighter since suffering the only defeat of his brief professional mixed martial arts career to Frank Mir in February 2008.
He will have his chance to prove it Saturday night when the two meet for the undisputed Ultimate Fighting Championship heavyweight title in the main event of UFC 100 at Mandalay Bay.
The loss came in Lesnar's second pro MMA fight and his first in the UFC.
"It's been a year and a half, and I think I've evolved rather well under the circumstances," Lesnar said. "They threw me to the lions right away, and that's how I wanted it."
Lesnar (3-1) said he did not execute his game plan in the loss to Mir. Instead of keeping the fight standing up, Lesnar relied on instinct and immediately took the dangerous jiu-jitsu specialist to the ground.
Though Lesnar pounded on Mir for more than a minute, he eventually was caught in a knee bar and forced to submit 1:30 into the bout.
Lesnar insists it won't happen again.
"I think you'll just see a guy that's going to be patient," he said. "It only takes one punch, and I'll find the right time to issue that."
Since that loss, Lesnar has risen to the top of the heavyweight division.
He first dominated Heath Herring for three rounds to gain a unanimous decision over the veteran. Then, Lesnar showed he had arrived by knocking out UFC legend Randy Couture to take the title in November.
"There's a lot of responsibility with being a champion now, so I definitely have to elevate my game," he said.
Mir, too, has used the first bout with Lesnar as a springboard. The victory gave him the opportunity to fight Antonio Rodrigo Nogueira for the interim heavyweight title in December.
Despite being a sizable underdog, Mir knocked out Nogueira early in the second round, setting up Saturday's unification bout.
After the victory over Nogueira, Mir looked right at Lesnar in the audience and called him out, saying, "You have my belt."
Mir and Lesnar have traded verbal barbs through the media in recent weeks.
Lesnar claims he doesn't want to get caught up in the rivalry or the fact that the rematch will headline the historic card.
"It's just another fight to me," he said. "I don't want to go into this fight with any more emotion than necessary. I just have to go in and stay calm."
Lesnar, who will turn 32 on Sunday, said part of his ability to remain calm comes from the fact that he finally feels at peace with his life.
In the past, he has complained of the lifestyle that he was drawn into when he was one of the biggest stars in World Wrestling Entertainment. There, he was constantly traveling and performing several nights a week.
By most accounts, Lesnar was doing better financially as a professional wrestler, but he said he simply was not happy.
"When I left the entertainment business, by any standard I guess I was doing all right," he said. "I guess it really broke down for me to being able to get in and do something that I really wanted to do and enjoyed doing. That's why I feel so fortunate to be a part of this: to be able to actually do something that I love and enjoy and to get paid for it, as well."
Fighting for real in the UFC also enables Lesnar to be home with his wife, Rena, in rural Alexandria, Minn., far from the public eye. The couple just had their first child, a son, and each has a daughter from a previous relationship.
"I'm so relaxed and so calm. I'm in a really good place in my life. I'm very grounded. I'm not searching to be someone I'm not. When I was a pro wrestler, I was living two, three, sometimes four different lives," Lesnar said. "So, I'm not soul-searching every day. I found who I am.
''I'm a fighter, and I'm happy with that. I work for a great company. I've got a great wife and great kids. A lot of people search for a hell of a long time, so I'm pretty fortunate."
Lesnar and his wife try to remain as private as a star athlete and three-time Playboy cover model possibly can, but he said dealing with the spotlight is the one thing he has brought with him from wrestling.
"That's why I have a simple life, because I've already been through that," he said. "I've already made a lot of money, and now it's just a matter of staying grounded, being close to my family and being happy."
Contact reporter Adam Hill at email@example.com or 702-224-5509.