Conor McGregor is one of the best fighters in UFC history, there is no doubt about it.The Irishman has been a world champion at both featherweight and lightweight and has won 22 of his 26 fights.McGregor has never lacked confidence and that was on full display yesterday as he ranked the four greatest fighters of all-time.He dubbed Anderson Silva the best UFC fighter ever, while he had Georges St-Pierre and Jon Jones in third and fourth respectively.McGregor revealed his belief that he is the second greatest fighter the sport has ever seen."My array of finishes, across 3 divisions, with champion status in 2, I’m No.2. If not tied 1," he said of himself."However still active, No.1 is fully secured by career end. And easily."There was no room in McGregor's 'Goat thread' for his biggest rival, Khabib Nurmagomedov.McGregor was asked about his exclusion and he was rather brutal with his comments."Fancy record but a way to go before any GOAT entry," he said of Khabib. "Only HL is win over me with hangover and broken foot."Other than that, made Iaquintas career with bad performance before Cerrone ended it again. 3rds to get Poirier out. 0 array of finishes. Bottled many bouts. Zero else of note."

Khabib has now taken to Twitter to berate McGregor's 'Goat thread'.

"You tapped out in featherweight, you tapped out in lightweight and you tapped in welterweight, you never defended title in the UFC or Cage Warriors, you gave up more than GSP, Spider and Bones all together.

"You greatest UFC fighter in Twitter history."

Brutal. Khabib was never going to be pleased with McGregor's rankings and he's destroyed his rival in response.

Another one of McGregor's rivals, Nate Diaz, was also unhappy.

Diaz posted photos of his victory over McGregor, with the caption: "Smoked the #1 p4p and double champ. Know the real goat when you see him.

"And don’t forget I did it better and quicker than anyone else on the ground and sent him down with punches quicker than Mayweather did so f**k all y’all rankings and know a real goat when you see me."