The 10 greatest men's MMA fighters of the 21st century have been ranked and some huge names are missing

The 10 greatest men's MMA fighters of the 21st century have been named and ranked - and some huge names are missing.

ESPN recently named the 100 best professional athletes of the 21st century, with the No.1 pick a controversial decision.

The outlet has now named and ranked the 10 greatest men's MMA fighters of the same era, leaving out some very accomplished UFC legends.

Former UFC welterweight champion Kamaru Usman, who made five defences of the 170lbs title during his reign as champion, is ranked 10, ahead of former two-weight UFC champions BJ Penn and Randy Couture.

MMA icon Fedor Emelianenko, who never fought in the UFC, Khabib Nurmagomedov and Demetrious Johnson are ranked sixth, fifth and fourth respectively.

Despite never stepping foot inside the famed Octagon, Emelianenko beat the likes of Antonio Rodrigo Nogueira, Mark Coleman and Kevin Randleman.

Former UFC lightweight king Nurmagomedov went his entire MMA career without tasting defeat, beating the likes of Conor McGregor, Dustin Poirier and Justin Gaethje.

Fedor Emelianenko during his fight against Dan Henderson. Image: Getty

Johnson dominated the UFC flyweight division at the peak of his powers, making eleven successful defences.

Ex-UFC middleweight champion Anderson Silva is ranked third, behind Georges St-Pierre, who won UFC championships in the welterweight and middleweight divisions.

According to ESPN, Jon Jones is the greatest men's MMA fighter of the 21st century.

Check out the top ten below:

First: Jon Jones

Second: Georges St-Pierre

Third: Anderson Silva

Fourth: Demetrious Johnson

Fifth: Khabib Nurmagomedov

Sixth: Fedor Emelianenko

Seventh: Randy Couture

Eighth: Chuck Liddell

Ninth: BJ Penn

Tenth: Kamaru Usman

But the likes of Daniel Cormier, who won UFC titles in the light-heavyweight and heavyweight division, and Jose Aldo have been snubbed of a spot in the top ten.

Aldo reigned over the UFC featherweight division before succumbing to McGregor.

Not to mention Tito Ortiz, Matt Hughes and Max Holloway, among others.