That's according to UFC president Dana White who says McGregor was released from hospital on Wednesday after undergoing surgery.
He expects the Irishman to be out of action for the rest of 2021, telling TMZ Sports he will be 'back in a year'.
White said: "I think they just released him right now from the hospital about 10, 15 minutes ago.
"He'll be in L.A. for a little while, and I don't know if he's going to fly home or what he's going to do from there.
"He'll be back in a year - yeah."
McGregor lost his second straight fight to Poirier, losing a doctor's stoppage last weekend.
He snapped his lower leg in the first round, with 'The Diamond' taking home the win to make it 2-1 in their series.
McGregor appears to want a fourth meeting, with White also keen on another match-up between the UFC lightweight stars.
Speaking after his surgery, the 33-year-old said: "What's up, fight fans. The 'Notorious' here.
"Just out of the surgery room, everything went to plan. Everything went perfect. I'm feeling tremendous. We've got six weeks on a crutch now and then we begin to build back.
"I want to thank all the fans all around the world for your messages of support. I hope you all enjoyed the show. I want to thank all the fans in attendance at the T-Mobile Arena - 21,800 fans in attendance.
"The place was absolutely electric. It was a hell of a first round. It would have been nice to get into that second round and then, you know, to see what's what.
"But it is what it is, that's the nature of the business. It was a clean break of the tibia and it was not to be.
"Dustin, you can celebrate that illegitimate win all you want, but you've done nothing in there. That second round would have shown all.
"Onwards and upwards we go, team. We dust ourselves off, we build ourselves back and we come back better than ever. Let's go, team."
In the meantime, Poirier, who is riding a three-fight winning streak, could compete against UFC lightweight champion Charles Oliveira in his next outing.
Featured Image Credit: PA/TMZ
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