McGregor knocked out Poirier in the first round of their featherweight clash in 2014, before his opponent reversed the result this January, stopping the Irishman in the second round of their lightweight rematch.
In July, the rivals fought for a third time – again at lightweight – with McGregor breaking his leg at the end of the first round to lose via doctor stoppage.
The irate Irishman stressed that the pair’s rivalry wasn’t over, but with Poirier challenging Charles Oliveira for the lightweight title this weekend, Whittaker has said McGregor should move on and seek other fights.
“You’ve got to ask, what are we going to see? Conor and Poirier 7, 8, 9?” Whittaker said on Fox Sports.
“Are they only going to fight each other for the rest of their career?
“Come on mate, give it a rest,” Whittaker told McGregor, who is still recovering from the injury he suffered against Poirier in July.
Whittaker outpointed Yoel Romero in a five-round war in July 2017 to win the interim UFC middleweight title, before becoming undisputed champion when Georges St-Pierre vacated his belt at the end of the year.
In July 2018, Whittaker retained the title by again beating Romero via decision, with the extremely close nature of the fight – and that of the pair’s first meeting – leading many fans to call for a trilogy bout.
Whittaker, who suffered injuries in each of his clashes with Romero, never fought the Cuban a third time. However, the Australian sympathised with compatriot Alexander Volkanovski, whom many fans wish to see take on Max Holloway for a third time – despite a 2-0 scoreline in Volkanovski’s favour.
The Australian comfortably outpointed Holloway in December 2019 to win the UFC featherweight title, before controversially beating the Hawaiian via decision again the following summer.
“Some people are gifted a lot of opportunities ... 0-9 and they’re looking for that 10th rematch,” Volkanovski said on Fox Sports.
Whittaker jokingly added: “A hundred percent that’s what we’re going to see; both Max and Alex are going to be [fighting each other until they’re] like 43.”
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