Take a look at our four in-depth profiles of some of the greatest UFC champions in history.
Undoubtedly one of the most entertaining fighters in the history of MMA, Anderson Silva to this day holds the record for the most finishes in UFC title fights and at nearly eight years, holds the record for the longest title reign.
The Greatest: UFC champions - Anderson Silva
Still the only fighter in UFC history to have fought more than 10 times and retained a 100% winning record. Despite battling injuries that stalled his journey to the top, Nurmagomedov enjoyed nearly three years as UFC lightweight champion, and no champion has ever looked less like losing their crown.
The Greatest: UFC champions - Khabib Nurmagomedov
Indisputably the greatest female fighter of all time, Amanda Nunes stands fourth on the list of longest UFC title reigns, and her combined reigns across the bantamweight and featherweight divisions of more than 3,500 days would far eclipse Anderson Silva's middleweight reign.
The Greatest: UFC champions - Amanda Nunes
UFC president Dana White once said that women would never compete in the UFC. The ascent of Ronda Rousey changed all that, with Rowdy leading the way for female fighters in the UFC less than two years later. At her peak, Rousey was the most dominant fighter the UFC had ever seen, winning all four of her five UFC title fights in the first round, and and three of them coming inside the first minute.
The Greatest: UFC champions - Ronda Rousey