The Irish superstar flirted with the squared circle back in 2017 when he was stopped by Floyd Mayweather, and his name continues to be linked to more big fights against the likes of Manny Pacquaio and Oscar De La Hoya. 

This Saturday, McGregor participates in the familiar surroundings of the octagon as he tackles Dustin Poirier for a third time.

Shields, now also an MMA athlete after great success in boxing, believes the former UFC champion needs to be 100% focused on the Octagon this time around if he is to win his head-to-head with "The Diamond" 2-1.

“It doesn’t matter who you are,” said Shields when speaking to Sky Sports. “You can be me, you can be Conor, you can be Floyd, he has to get his mind back to MMA. He has to get his mind off boxing. You can’t be in a boxing stance in MMA.  

“If he can back to his wrestling and all that stuff, I think he can beat Dustin Poirier. I feel like Dustin Poirier has his [McGregor’s] number right now unless McGregor goes back to the drawing board and switches his mind back to MMA.”