When Cain Velasquez and Junior dos Santos meet in Saturday night's heavyweight title fight in UFC's debut on Fox, it will mark a rare situation in which the best two consensus heavyweights in the world go at it.
Velasquez and Dos Santos represent the modern evolution of the complete heavyweight fighter. They are not one-trick ponies, or even two-trick ponies. They have their specific strengths, but both are complete in every aspect of their games.
In looking back at the history of the heavyweight division over the 18 years of the modern incarnation of mixed martial arts, there have been a number of key heavyweight battles, but only a few meetings of the true big two at the time.
They weren't all pretty, or even exciting. But these fights, and a few others, shaped the evolution of the division and lead us to Saturday's showdown. Here's a look at the key bouts in MMA heavyweight history:
KEN SHAMROCK vs. DAN SEVERN (May 17, 1996, Detroit): Shamrock was the defending Superfight champion, the forerunner to what would later be called the UFC heavyweight championship. He was a wrestler who had learned submissions and had some stand-up training.
Severn, a few weeks before his 38th birthday, was one of the best heavyweight wrestlers in the world. Using almost only wrestling, he had run his way through most of his UFC competition. He had just won the "Ultimate Ultimate" tournament, which was then the UFC's biggest tournament.
They had met once before, on July 14, 1995. Shamrock had then used a standing guillotine to choke out Severn in just 2:18 in a match to determine UFC's first singles champion.
A sellout crowd of 11,000 pro-Severn fans (Severn lived in nearby Coldwater, Mich.) came to Cobo Arena for the rematch, but the event itself was in doubt. During fight week, Michigan politicians attempted to shut the show down, and matters ended up in court just hours before the fight was to take place. A local judge ruled the event could continue, as long as closed fist punches and head-butts (still legal at the time) were banned. UFC owner Bob Meyrowitz agreed to the deal, and the show went on. The fighters were told that referee John McCarthy would warn them if they punched, but they could do so at will and not to take the ban seriously.
With the new rules in place, both fighters adopted a counter-fighting strategy. So they stood there and circled. And circled. And circled. This went on for roughly 28 minutes of a scheduled 30-minute fight. Fans pelted the cage with garbage and chanted "Let's go Red Wings," while neither fighter would commit to anything. Severn would later call it the ultimate battle of wills.
Shamrock's viewpoint was more akin to most, saying it was the worst fight of all-time. When they actually did fight, both had brief periods on top of the other, with Severn doing slightly more damage and winning the title by split decision.
UFC officials were so appalled by both the fight and Severn, who they didn't consider marketable, as champion, that they pulled the singles title from all upcoming shows. Severn wasn't brought back until they were confident they had someone who could beat Severn. That someone was Mark Coleman, a younger wrestler in his competitive prime, and on February 7, 1997 he won the title from Severn.
The top two heavyweight fighters in MMA rarely clash, but when they do it is often an upset.
MARK COLEMAN vs. MAURICE SMITH (July 27, 1997, Birmingham, Ala.): Coleman, as UFC heavyweight champion, had looked unbeatable in winning two straight tournaments and then the heavyweight title, and he was considered No. 1 in the world at the time. Smith was a former kickboxing champ and held the title of Extreme Fighting Championships, a rival pay-per-view group that had just folded, and thus this was considered the championship unification match.
Nobody thought Smith had a chance. In those days, MMA had been the province of wrestlers and jiu-jitsu practitioners. Up to that point, stand-up fighters had been useless because the wrestlers would take them down and keep them there.
But Smith and his coach, Frank Shamrock, noticed a weakness in Coleman. Coleman was a world-class wrestler, a 1992 Olympian who entered the sport after Kurt Angle beat him for a slot on the 1996 Olympic team. But wrestlers were used to going seven minutes, while UFC rules at the time had title fights going 21 minutes. In preflight interviews, Smith goaded Coleman by saying he punched like a girl.
[ Related: Network debut is UFC ‘s dream come true ]
Mad about the remarks, Coleman immediately took Smith down and threw everything into his punches on the ground. Smith just bided his time against his overly aggressive foe, waiting for Coleman to gas out. Once Smith managed to get to his feet, he picked Coleman apart for the rest of the fight to win a decision. Smith not only became the first stand-up fighter to hold a UFC championship, but taught a valuable lesson: As important as wrestling and submissions are to a fighter, cardio also plays a major role at the top level.
ANTONIO RODRIGO NOGUEIRA vs. FEDOR EMELIANENKO (March 16, 2003, Yokohama, Japan): By 2003, Japan became the center of the MMA world and the top heavyweight was the Brazilian-born Nogueira. He exploded onto the scene by winning a 32-man tournament in the RINGS promotion to become its heavyweight champion, and then signed with PRIDE and became its heavyweight champion. Nogueira had a 19-1-1 record and his only loss coming at the hands of Dan Henderson in a controversial decision. His combination of boxing and submission skill made him the new state-of-the-art heavyweight fighter.
Emelianenko, who followed Nogueira into PRIDE after winning the next RINGS tournament, was not considered a threat to the "unbeatable" Nogueira at the time. But Emelianenko proved to have the perfect style to knock Nogueira off. While not as good technically in boxing, Emelianenko was a harder hitter and could do more damage. More important, unlike the wrestlers who would take Nogueira down and get swept and usually submitted, Emelianenko had enough takedown ability and knowledge of submissions to where he could stay on top and inflict damage without leaving a limb open. Emelianenko took the unanimous decision and the "Fedor Era" began.
FEDOR EMELIANENKO vs. MIRKO "CRO COP" FILIPOVIC (August 28, 2005, Saitama, Japan): Emelianenko had maintained his title for two-and-a-half years when the former Croatian kickboxer emerged in Japan as the most popular foreign fighter. From the start of Emelianenko's title run, Japanese fans wanted a Fedor vs. "Cro Cop" match. But for two years, circumstances got in the way, largely Filipovic suffering two losses, and Emelianenko having repeated hand injuries.
"Cro Cop" went on a run where he had 11 of 12 wins against most of the best heavyweights of that time, all ending in less than 5:00. The belief was "Cro Cop" could have strong enough takedown defense to keep it standing, and on their feet, his kickboxing would take Emelianenko apart, knocking him out like he had almost every other opponent. But if Emelianenko could get it to the ground, he could finish Filipovic quickly.
Thirty-five thousand fans packed the Saitama Super Arena for the showdown, a rare crowd that was drawn by two foreigners in Japan, where conventional wisdom held you had to have a native fighter in the main event to draw big. Because the match had been delayed so long, Filipovic's chase of the title garnered incredible interest by the Japanese public who believed their favorite would win the big one.
With each knockout, the build for the big match gained more interest. Filipovic's catch phrase, "right leg, hospital, left leg, cemetery" was a wildly popular saying and interest picked up considerably when the Croatian's left high kick knocked out Fedor's much larger brother, Alexander, in just 2:09 on August 15, 2004.
When the much-anticipated match finally happened, it went completely different than expected. With much of the fight taking place on the feet, Emelianenko was able to move forward and "Cro Cop" could not attack well off his heels. When it got to the ground though, Emelianenko's powerful ground and pound was largely negated by Filipovic's surprisingly strong ground defense. What nobody expected was a fight that would go the distance. Emelianenko retained his title in what would end up being the high point of his career.
TIM SYLVIA vs. RANDY COUTURE (March 3, 2007, Columbus, Ohio): This UFC heavyweight title fight was not a battle of No. 1 vs. No. 2 as Emelianenko's shadow was still strong. Still, this emotional evening was so memorable that it merits inclusion. Sylvia, at 6-foot-8 and 260 pounds, was champion. Couture, who had held the title twice between 1997-2002, was just shy of his 44th birthday and had retired after losing two of his three previous fights at light heavyweight.
UFC had learned through business triumphs and failures that whenever possible, they should give the fans the fight they want to see.
[ Related: White touts both MMA and boxing ]
Sylvia, at the time, was expected to face Gabriel Gonzaga in a fight that would have bombed at the box office. Couture had expressed interest in returning to action, and said he believed he could beat Sylvia. Given his age and the huge size disadvantage, few believed him, but clearly the fans wanted to see it.
Couture's announcement of his return led to a ticket-buying frenzy. A then-UFC record crowd of 19,079 fans (still the U.S. record) packed the Nationwide Arena for the UFC's most emotional fight ever. Couture knocked Sylvia down with his first punch and dominated all five rounds en route to a decision. The crowd counting down the final seconds of the fifth round and the immediate celebration afterwards was reminiscent of Times Square on New Year's Eve. To this day, when people talk about the hottest crowd in UFC history, this fight is still the measuring stick.
RANDY COUTURE vs. BROCK LESNAR (November 15, 2008, Las Vegas): For this one, Couture was 45 and coming off a legal dispute with UFC. He had been out of action for more than one year. Despite a 2-1 record, Lesnar was given a title shot because there were no other viable contenders ready (the logical opponent, Nogueira, was already booked for a fight the next month with Frank Mir), and because his name value meant huge business.
The fight ended up being the second biggest pay-per-view fight in UFC history up to that point. One reason is that beforehand, virtually everyone was certain it would be a slaughter. But people couldn't agree on who would do the slaughtering.
One camp said Lesnar was a joke of a fighter, a fake pro wrestler and Couture had forgotten more than Lesnar would ever know – they said it would be embarrassing the difference in skills. The other side thought Lesnar was too young, too big, too strong and too athletic. And that camp proved to be correct, with Lesnar scoring the TKO at 3:07 of the second round.
BROCK LESNAR VS. CAIN VELASQUEZ (October 23, 2010, Anaheim, Calif.): After winning the title, Lesnar became the biggest drawing card the sport had ever seen. Velasquez, meanwhile, was signed by UFC after only two pro fights because of his reputation among those who trained with him as being the most talented heavyweight in the sport. Most insiders knew a showdown was inevitable.
Velasquez was giving up considerable size to Lesnar, but was the same caliber of wrestler as Lesnar, and far superior in every other aspect of the game. He was able to immediately get up from Lesnar's takedowns, score his own takedowns and send the champion reeling from punches standing. When he continued his punching attack on the ground, Lesnar was left helpless and the fight was called off at 4:12 of the first round. Velasquez's win brought one of the loudest crowd reactions in years. Saturday's fight, which will join this list of the biggest heavyweight battles in history, will take place in the same venue, the Honda Center in Anaheim, Calif.
Other popular stories on Yahoo! Sports:
• Legend Joe Frazier defined what it means to be a fighter
• Joe Frazier's rivalry with Ali was one of the greatest in sports history
• Video: Honoring cancer research at A Day of Champions