CONOR MCGREGOR won’t be making his blockbuster return to the octagon at UFC 300, according to his head coach and mentor John Kavanagh.

McGregor, 35, was on course to headline the upcoming historic card after the UFC decided to keep him on the shelf for the six months he would’ve required to have been in the USADA testing pool following his October re-enrolment.

Conor McGregor hasn’t set foot inside the octagon in nearly two-and-a-half yearsCredit: AP

The Notorious was seemingly set to headline UFC 300 in AprilCredit: GETTY

The Irishman’s head coach John Kavanagh has revealed the promotion want him back in the summerCredit: SPORTSFILE

UFC president Dana White, however, seemingly poured cold water on the prospect of The Notorious topping the bill of the April card last week.

And Coach Kavanagh has claimed the promotion are now looking to have the Irishman headline their International Fight Week card in July.

During an appearance on The MMA Hour, he told Ariel Helwani: “We were hoping for April.

“That was the hope, that’s what we were told and now it seems to be the summertime.”

Team McGregor have been left stumped by the UFC brass’ change of plans.

SBG Ireland head coach Kavanagh said: “I don’t know [why], that’s what were having a bit of a back and forth about today.

“And I think he said you suggested that maybe 300 is already big enough [to not have him headline it].

“At least your reasoning had some logic. ‘Okay, do we really need him for UFC 300 that’s gonna be such a massive event?’

“So, are they holding him back for International Fight Week? I don’t really know.”

An emotional McGregor publicly pleaded with UFC chiefs to give him a date for his comeback clash against Michael Chandler last month.

“He’s very frustrated,” Kavanagh said of his most famous student. “I was [worried about his mental health] too.

“But hearing him today – and he’s found this great group of training partners. At least he’s doing that.

“Okay, it’s not the same as getting to compete in front of a large crowd but at least he’s getting training in. And that’s so important.

“We heard Volk [Alexander Volaknovski] talk about that, keeping busy.

Conor McGregor hasn’t set foot inside the octagon since breaking his legCredit: AP

“So I love to hear that he’s training hard with these guys.”

Frustrations at the delay aside, Kavanagh is happy former two-division champion McGregor will have more time to prepare for what will be a blockbuster return to the cage.

He said: “I told him, ‘It’s a knockback hearing that we were hearing it was April and now it’s July

“‘But it’s not the end of the world. It is an extra couple of months.

“‘It’s not great, but hey, you’re enjoying your training at the moment. Let’s just keep that going.'”

McGregor – the first fighter to hold two UFC belts simultaneously – hasn’t set foot inside the octagon since breaking his left leg in his trilogy fight with Dustin Poirier nearly two-and-a-half years ago.

Conor McGregor will be welcomed back to the octagon by Michael ChandlerCredit: TWITTER@THENOTORIOUSMMA