There are a dozen or so weight classes in mixed martial arts and dozens of fighters competing in each one across multiple promotions, including the UFC, Bellator, One Championship and the Professional Fighters League.
Here’s a look at the 10 best MMA fighters across the entire landscape of the sport, regardless of division or promotion, presented in reverse order.
10. Dustin Poirier (UFC, 25-5, 1 NC)
Poirier's four most recent opponents: Max Holloway, Eddie Alvarez, Justin Gaethje, Anthony Pettis. All were either reigning or former champions in the UFC and/or other MMA promotions. Poirier won all four bouts, with three finishes. In his April bout at UFC 236, he beat Holloway to win the interim lightweight title and set up a unification bout with Khabib Nurmagomedov this September.
9. Stipe Miocic (UFC, 19-3)
Miocic became the fourth person to win back his UFC heavyweight championship when he finished Daniel Cormier at UFC 241 on Aug. 17. It was his first fight in more than a year, and a rematch against the man who took his title from him. Miocic is considered by many to be the greatest heavyweight champion in the UFC, having successfully defended his title a record three consecutive times.
8. Max Holloway (UFC, 21-4)
The reigning UFC featherweight champion had his 13-fight winning streak ended last April when he moved up to challenge Dustin Poirier for the interim lightweight title. But he maintains a 14-fight win streak at featherweight after he defended his title against Frankie Edgar at UFC 240. Holloway won the bout via unanimous decision, 50-45, 49-46, 48-47.
7. Daniel Cormier (UFC, 22-2, 1 NC)
A year ago at this time, Cormier was the holder of two UFC titles. He since vacated the light heavyweight title and then lost the heavyweight title to Stipe Miocic at UFC 241 on Aug. 17. Cormier, 40, was ahead on all three judges’ cards (30-27, 30-27, 29-28) going into the fourth round before Miocic connected with a few body shots that set up the final knockout strikes.
6. Amanda Nunes (UFC, 18-4)
Amanda Nunes' resume en route to becoming UFC bantamweight champion included wins over Ronda Rousey, Miesha Tate and Valentina Shevchenko (twice). She can add to that list a win over Cris Cyborg, as Nunes knocked out who many had considered the best female fighter in MMA history at UFC 232. And she did so in 51 seconds to become the featherweight champion and first female two-weight champion in UFC history. She then defended her bantamweight title with a first-round TKO of Holly Holm on July 6 at UFC 239. Her next defense is set for UFC 245 on Dec. 14 against Germaine de Randamie.
5. Tony Ferguson (UFC, 25-3)
He's on a 12-fight win streak over the past seven years and should be next in line for a lightweight title shot after this September. That win streak for Ferguson, the former interim champion, includes nine finishes, most recently against Donald Cerrone at UFC 238 and Anthony Pettis at UFC 229.
4. Demetrious Johnson (One, 29-3-1)
After his "trade" to One Championship, Demetrious Johnson continued to do what he did in the UFC: Win. He submitted Yuya Wakamatsu in the second round of his One debut last March, then won a decision over Tatsumitsu Wada in August. That was his first bout since losing the UFC flyweight title by split decision to Henry Cejudo, which ended a UFC-record streak of 11 consecutive title defenses.
3. Henry Cejudo (UFC, 15-2)
There was a time when Cejudo found himself staring at back-to-back losses. Now, with a five-fight win streak that has yielded him both the UFC flyweight and bantamweight titles, he factors into the latest rounds of conversation about the pound-for-pound best. His win streak includes opponents Demetrious Johnson, TJ Dillashaw and Marlon Moraes. He's out for a while now after having shoulder surgery.
2. Khabib Nurmagomedov (UFC, 27-0)
Nurmagomedov has never lost an MMA fight, and he's had 27 of them as a professional. In this sport, that's borderline impossible, no matter what anyone wants to say about level of opponent. Nurmagomedov finally lost his first round — round! — in the UFC when defending his lightweight title against McGregor. He'll put that streak on the line again in a title unification bout against interim champ Dustin Poirier at UFC 242 in Abu Dhabi on Sept. 7.
1. Jon Jones (UFC, 25-1, 1 NC)
The only reason Jones hasn't sat atop this list every day for the past seven years or so has been his own out-of-cage antics that got him into trouble on multiple occasions with multiple legal and non-legal organizations. When he's fighting, he's the best and it's unquestioned. He proved it again at UFC 235 by completely shutting down any attempt at offense by Anthony Smith. He then won a split decision over Thiago Santos at UFC 239 on July 6.
On the outside looking in
11. Valentina Shevchenko, UFC women's flyweight champion
12. Robert Whittaker, UFC middleweight champion
13. Ryan Bader, Bellator light heavyweight and heavyweight champion
14. Kamaru Usman, UFC welterweight champion
15. Tyron Woodley, UFC welterweight
16. Israel Adesanya, UFC interim middleweight champion
17. Paolo Costa, UFC middleweight
18. Cris Cyborg, featherweight
19. Jessica Andrade, UFC women's strawweight champion
20. Yoel Romero, UFC middleweight