Brock Lesnar: Top 10 Moments of His Multi-Sport Career

Before Brock Lesnar became a dominant UFC Heavyweight Champion, he was cut by the Minnesota Vikings.

Before Lesnar's short stint in the NFL, he was the "Next Big Thing," rocketing to the top of the WWE.

And before his time in the WWE, Lesnar was a national champion in wrestling for the University of Minnesota.

In honor of Saturday's bout at UFC 121 between himself and undefeated Cain Velasquez for the heavyweight crown, here are some of the reclusive champion's greatest moments in all of his career ventures.

2000 NCAA Heavyweight Wrestling Championship

A two-time All-American and All-Big Ten selection, Lesnar entered his senior year looking for a national championship. In 1999, he lost in the finals to Stephen Neal, an eventual offensive lineman for the New England Patriots.

Much like he has proved time and time again in the "Octagon," Lesnar dominated his opponent in the 2000 NCAA Finals, defeating Wes Hand of Iowa to win the 285-pound title.

WWE Debut (March 18, 2002)

After graduating from Minnesota, Lesnar was signed by the WWE.

About 18 months after his NCAA victory, he made his debut in the company as the "Next Big Thing," with real-life friend Paul Heyman as his manager.

Here's his debut with the company on the night after WrestleMania X8 in Toronto.

WWE Undisputed Championship (Aug. 25, 2002)

Just five months after making his WWE debut, Lesnar was booked to defeat the Rock at SummerSlam to win the WWE Undisputed Championship.

At 25 years of age, he became the youngest WWE Champion in the history of the promotion, holding the belt until Nov. 17 via a defeat against The Big Show.

However, it would be far from Lesnar's only championship reign in the company.

Ring Collapses During Match With Big Show (May 2003)

This earns a spot on the list simply because of the sheer force of Lesnar suplexing the near 500-pound Big Show off the turnbuckle, causing the ring to collapse.

If anything else, it makes for one cool video.

WWE Championship (Sept. 18, 2003)

Lesnar's third WWE title reign began in possibly his most impressive match inside the squared circle.

In the Sept. 18, 2003 episode of SmackDown!, Lesnar defeated Olympic gold-medalist Kurt Angle in a 60-minute "Iron Man" match to win the title.

MMA Debut (June 2, 2007)

After leaving the WWE to pursue a failed NFL career with the Minnesota Vikings, Lesnar announced in 2006 that he would enter the world of mixed martial arts.

The "Next Big Thing" made his debut at K-1 Dynamite!! USA, facing Min-Soo Kim after seven-footer Hong Man Choi bowed out due to injury.

However, Lesnar's strategy did not change, as he recorded a first-round knockout.

It would be his only fight in K-1, as the UFC came calling soon after.

UFC Debut Vs. Frank Mir (Feb. 2, 2008)

It was far and away the most anticipated debut in the history of the UFC. While his professional wrestling background earned him credibility with casual sports fans, there was talk that Dana White was bringing in a "sideshow" attraction.

Why does Lesnar get such a big opportunity after just one fight?

In his debut at UFC 81, Lesnar proved he belonged in the Octagon. Engaging in a 90-second slugfest with Frank Mir, the "Next Big Thing" looked dominant until Mir put Lesnar in a knee bar. He tapped almost immediately, displaying a lack of a submission defense.

UFC Heavyweight Championship (Nov. 15, 2008)

After taking Heath Herring to a decision at UFC 87 on Aug. 9, 2008, Lesnar controversially earned a title shot against Randy Couture at UFC 91.

Once again, MMA experts wondered why Lesnar received such an opportunity with so little experience.

Like he did against Mir, Lesnar proved he belonged inside the Octagon with a second-round knockout of the UFC Hall of Famer.

First Submission Victory (July 3)

After fighting a near-fatal case of diverticulitis and mononucleosis, Lesnar returned to the Octagon at UFC 116 in the most anticipated comeback in the promotion's history.

In the fight against interim heavyweight champion Shane Carwin, the champion debuted a new aspect of his game that was previously non-existent.

Taking advantage of Carwin's poor stamina and inability to finish the fight in the first round, Lesnar was able to put his fatigued opponent in an arm triangle choke, earning a second round victory via submission.

Lesnar-Mir II (July 11, 2009)

Lesnar's rematch with Frank Mir was the main event at UFC 100

Lesnar looked like his old self, knocking out Mir in the second round.

Any moments you want to see added to this list? Comment below.

Ryan Papaserge is a junior Journalism/Mass Communication student at St. Bonaventure University and a writing intern at Bleacher Report.