Very few fighters in the history of mixed martial arts have been more consistently exciting than "The Phenom" Vitor Belfort. In each of his fights, Belfort is almost guaranteed to do whatever he can to ensure a knockout victory.

RELATED: 14 Fastest Knockouts In UFC History

For over two decades, Belfort has been a threat in three different weight classes and has fought some of the best fighters in UFC and around the world. Belfort’s MMA career was filled with title fights, memorable knockouts, and rivalries. However, his career was also filled with controversy. Without a doubt, Belfort has had a legendary MMA career filled with moments that every fight fan should be aware of.

10 UFC Heavyweight Tournament

Belfort Silva

At the age of 19, Vitor Belfort made his mixed martial arts debut. In just 12 seconds, Belfort won his fight by knockout following a barrage of punches.

RELATED: 5 Best Tournaments In MMA History (& 5 Worst)

With an impressive MMA debut, Belfort was invited to compete in the UFC. At UFC 12, Belfort competed in a one-night, four-man, heavyweight tournament. With a total fight time of just two minutes, Belfort defeated both of his opponents by technical knockout. Belfort’s tournament win predates the days of the UFC Heavyweight Championship. As a winner of one of the original UFC tournaments, Belfort has a claim to being a former UFC Heavyweight Champion.

9 UFC Champion

Vitor Belfort UFC Title

At UFC 46, in 2004, Belfort would win his first official UFC championship when he defeated Randy Couture for the UFC Light Heavyweight Championship.

Belfort won the title due to a doctor stoppage after Couture suffered a cut on his eye. This was the second fight between Belfort and Couture. The two first met at UFC 15 in 1997. On that night, Couture handed Belfort his first MMA loss. After losing the light heavyweight title, Couture was given an immediate rematch in 2004. At UFC 49, Couture won the fight after the doctor ruled Belfort could not continue after the third round.

8 Run In PRIDE

Vitor Belfort PRIDE

On two separate occasions, Belfort left the UFC to compete in the biggest MMA promotion in Japan, PRIDE Fighting Championship. Belfort first competed in PRIDE in 1999. Fighting as a heavyweight, Belfort lost his debut in the promotion to Kazushi Sakuraba. Belfort would go on to win his next four fights which featured notable heavyweight wins against Gilbert Yvel and Heath Herring.

After returning to the UFC for five fights, Belfort would return to Japan for three more fights. However, his second stint in PRIDE was not successful. He suffered notable losses to Alastair Overeem and Dan Henderson.

7 Biggest Win Streak

Vitor Belfort
Jason Silva-USA TODAY Sports

The biggest win streak of Belfort’s career came after his last fight in PRIDE. Following his final fight in Japan, Belfort won two consecutive fights in the Cage Rage promotion in Europe. After those wins, Belfort returned to the United States to fight for the Affliction promotion.

In Affliction, Belfort earned knockout wins over Terry Martin and Matt Lindland. Belfort then returned to the UFC. In 2009, at UFC 103, Belfort knocked out former UFC Middleweight Champion Rich Franklin. Following his fifth consecutive win, Belfort was offered an opportunity to fight for the UFC Middleweight Championship.

6 Title Fights

Jon Jones Vitor Belfort
Tom Szczerbowski-USA TODAY Sports

After returning to the UFC in 2009, Belfort would fight for a UFC title on three separate occasions. Belfort fought Anderson Silva for the UFC Middleweight Championship at UFC 126 in 2011. Silva defeated Belfort after landing a legendary front kick to the face. After the loss, Belfort won his next two fights to earn an opportunity against Jon Jones and the UFC Light Heavyweight Championship. At UFC 152, in 2012, Jones submitted Belfort and kept his championship.

Following the Jones loss, Belfort went on one of the most impressive streaks of his career when he knocked out Michael Bisping, Luke Rockhold, and Dan Henderson in consecutive fights. As a result, Belfort was given a title opportunity against Chris Weidman. At UFC 187, in 2015, Weidman defeated Belfort by TKO to retain his title.

5 Dan Henderson Trilogy

Dan Henderson Vitor Belfort
Jason Silva-USA TODAY Sports

Randy Couture was not the only fighter Belfort fought three times in his career. Belfort also fought Dan Henderson on three different occasions.

The two first met in PRIDE in 2006. On that night, Henderson earned a unanimous decision victory. Their second encounter took place in the UFC in 2013. Belfort landed a vicious head kick in their second fight to earn the win. In their third meeting, Belfort once again won the fight following a head kick in 2015.

4 TRT

Belfort Weigh In
Joe Camporeale-USA TODAY Sports

Belfort’s MMA career, especially his final stint in the UFC, was filled with controversy due to his use of testosterone replacement therapy (TRT).

RELATED: Vitor Belfort (& 9 Other UFC Fighters Who Used TRT)

As Belfort got older, he began receiving TRT due to low levels of testosterone in his body. Some skeptics believed his past use of steroids, which he tested positive for following his first fight with Dan Henderson, led to his low testosterone levels. Other skeptics believe that lower testosterone is natural in life, and Belfort should not have received treatments to help him have the testosterone levels of much younger fighters.

3 MMA Retirement

Vitor-Belfort-UFC-
Jason Silva-USA TODAY Sports

After winning only one of his last five fights in the UFC, Belfort announced his retirement from the sport. At UFC 224, in 2018, Belfort was knocked out, once again by a front kick to the face, by former UFC Light Heavyweight Champion Lyoto Machida. Befort announced his retirement following the fight.

Prior to fighting Machida, Belfort won a decision against Nate Marquardt. Before his final UFC win, Belfort suffered three consecutive TKO losses to Jacare Souza, Gegard Mousasi, and Kelvin Gastelum.

2 Boxing

Belfort Walkout
Joe Camporeale-USA TODAY Sports

Last year, Belfort competed in an exhibition boxing match against legendary boxing champion Evander Holyfield. Belfort was originally going to fight Oscar De La Hoya, but the boxing legend withdrew from the fight after contacting COVID-19. It would take Belfort less than two minutes to win the fight against Holyfield.

The fight between Belfort and Holyfield was a boxing spectacle. The undercard saw a boxing match between former UFC champions Anderson Silva and Tito Ortiz. The event also featured celebrity commentators such as rapper 50 Cent and former United States President Donald Trump.

1 ONE Championship

Vitor Belfort Walkout
Jason Silva-USA TODAY Sports

While he did retire from the sport of MMA, do not be surprised if Belfort continues to fight in the future.

Just a few months after losing to Lyoto Machida and retiring from the sport, Belfort revealed he was interested in a return. In 2019, Belfort signed with ONE Championship and was scheduled to fight. However, the fight ended up not taking place, and he parted ways with the promotion without ever competing. At 45 years old, it will be interesting to see what comes next for the MMA legend.