After ranking the best fighters across all men's divisions in MMA history, the CBS Sports experts sat down to tackle the difficult task of ranking the 10 best fighters in history pound-for-pound. It has been a hot topic lately with Conor McGregor -- who made our list -- making claims on Twitter that he is the sport's greatest of all-time.
After debating and voting, the top three fighters were separated by the slimmest margin possible. But it was Jon Jones who emerged as the CBS Sports pick for MMA's all-time G.O.A.T., while McGregor came in at the No. 9 spot on the list. MMA remains a young sport, and there are some potential all-time greats active in the game right now, meaning this list could look vastly different in five years.
Again, this is based on resume and overall ability displayed inside the Octagon.
The ballots are in, and you can check out the rankings according to votes cast by Brent Brookhouse, Brian Campbell, Brandon Wise and Jack Crosby below.
10. Matt Hughes: The bottom spot in the rankings was competitive with many deserving contenders. In the last of Hughes' nine fights in 2001 (yes, nine fights in 12 months), he returned to the UFC to knock out Carlos Newton with a slam to win his first UFC welterweight title. Between his two runs as welterweight champ, Hughes had seven successful title defenses. In his most dominant years, Hughes picked up wins over Newton (twice), Sean Sherk, Georges St-Pierre, B.J. Penn and Matt Serra -- all men who at one point held UFC gold. That is a stellar -- and often overlooked -- resume.
9. Conor McGregor: McGregor has been vocal on social media lately over his status as MMA's greatest of all time. While he didn't crack the top five on the CBS Sports list, there's no denying he is one of the greats. McGregor is a global superstar not only because of his ability and willingness to promote himself, but because he is a dynamic, dangerous fighter. His march to the featherweight championship was one of the most impressive stretches in UFC history, culminating in a 13-second knockout of Jose Aldo. Adding the lightweight title with a knockout of Eddie Alvarez gave him the distinction of being the first ever fighter to simultaneously hold championships in two weight classes. If McGregor's resume has any weakness compared to others on the list, it is a lack of a championship legacy. While he won the featherweight and lightweight titles, he made no defenses of either championship.
8. Daniel Cormier: Cormier followed the McGregor path of holding two championships simultaneously, in his case light heavyweight and heavyweight. Cormier has toppled top fighters in both divisions across Strikeforce and UFC, defending the light heavyweight title three times and the heavyweight belt once. Cormier could never truly establish himself as the top light heavyweight in the world, however, losing to Jon Jones twice -- though one was ultimately ruled a no contest after Jones failed a drug test -- and his title reign was a product of Jones' failings more than anything. How Cormier's heavyweight championship rubber match with Stipe Miocic plays out will go a long way in determining his long-term legacy.
7. Jose Aldo: The Brazilian won 18 consecutive fights from 2006 to 2014. During that time, he established himself as the greatest featherweight ever. He won the WEC featherweight championship with a TKO of Mike Thomas Brown and defended the belt twice before being named UFC champ when the division was absorbed by the promotion. He made another seven defenses of the title before running into McGregor in 2014. He would go on to lose more fights in the following years, though only against Max Holloway and Alexander Volkanovski -- a pair of champions. A drop to the bantamweight division this past December resulted in a controversial split decision loss to Marlon Moraes and now Aldo looks to be getting set to face Petr Yan for the now-vacant bantamweight title. A late-career title win in a new division would add a new dimension to Aldo's resume.
6. Khabib Nurmagomedov: Nurmagomedov has been perfect as a professional. With a 28-0 record and almost every win a dominant performance, it's hard to find much to complain about with "The Eagle's" resume. If there is any shortcoming it is a lack of statement wins. Nurmagomedov's victories over McGregor, Rafael dos Anjos and Dustin Poirier are all good to borderline great, but he's still lacking marquee performance. That Nurmagomedov won the vacant belt with a win over Al Iaquinta doesn't help his overall legacy. Had Nurmagomedov's planned fight with Tony Ferguson not fallen through five times, he would have a second signature win to put alongside the McGregor thrashing. Keeping that all in mind, Nurmagomedov has been so dominant, and his legacy still is developing. He could be a top five all-time fighter by the time he hangs up the gloves.
5. Demetrious Johnson: Since dropping to flyweight, Johnson has rattled off a 16-1-1 record. For much of that time, Johnson was considered the top pound-for-pound fighter in the sport. After becoming the inaugural UFC flyweight champion, Johnson successfully defended the title 11 times. While fighting the best in the division, Johnson displayed unparalleled creativity in the Octagon. That he was never a big draw made it easy for the UFC to part ways with "Mighty Mouse" after he lost a controversial split decision to Henry Cejudo. But Johnson has continued to showcase his dominance in ONE Championship, winning their flyweight grand prix tournament.
4. Fedor Emelianenko: During PRIDE's heyday, Emelianenko was an unstoppable force at heavyweight. The Russian won 27 consecutive fights from 2001 to 2009, winning the PRIDE heavyweight title, dominating some of the best in the world -- including an amazing rivalry with Antonio Rodrigo Nogueira and a massive win over Mirko Cro Cop. His aura of invincibility was eventually shattered by Fabricio Werdum in 2010. The PRIDE method of matchmaking and never setting foot in the UFC Octagon has tarnished Emelianenko's legacy for many, but there should be no denying that his incredible run in the most dangerous division in the game placed him as one of the best to ever do it in the sport.
3. Georges St-Pierre: GSP is the greatest welterweight of all time, having won the UFC welterweight title twice and making nine successful title defenses. He only lost to two men in his career, Hughes and Serra, and made clear statements in rematches that he was the better man. His run saw him beat a murderer's row of contenders and show very few moments of weakness before retiring on top of the game after a brutal -- and controversial -- win over Johny Hendricks. But, returning to action after four years out of the sport to beat Michael Bisping and win the middleweight championship added a little something extra to his all-time standing.
2. Anderson Silva: A 17-fight winning streak and 10 successful title defenses give Silva the kind of resume that every man at the top of this list shares. Silva was a force of nature, seemingly playing a striking game that was light years ahead of the men he faced, no matter how talented the opponent. Silva also dipped into the light heavyweight division three times during his peak years, knocking out James Irvin, Forrest Griffin and Stephan Bonnar. Silva also didn't just beat men, he destroyed them while doing seemingly anything he wanted from bell-to-bell. The end of his peak came hard and fast, but for years, Silva was the best fighter in the world.
1. Jon Jones: Jones has lost one fight in his career -- a screwy disqualification to Matt Hamill -- but the majority of blemishes in his career have come from his own out-of-cage mistakes. Jones should be on a run of 14 or more consecutive title defenses, but he has been stripped of titles and had title wins overturned because of legal problems and failed drug tests. But in the cage, Jones is as brilliant a fighter as the sport has ever seen. Beyond his top-shelf wrestling or his dynamic striking, Jones is capable of making in-fight calculations and adjustments better than anyone in the sport. His position on the list also benefits from not having seen his peak end in the ways a Silva or Fedor's late-career losses have colored things. But, even if he never wins another fight, Jones has proven himself the best MMA has ever seen.