Scrapping Conor McGregor's huge comeback would be a DISASTER for the UFC... with showdown against Michael Chandler in doubt, who could replace main event at UFC 303?

It's looking increasingly unlikely that the long-awaited return of Conor McGregor will not be taking place at UFC 303 on June 29.

McGregor posted a cryptic video on his Instagram story on Thursday which showed his younger self talking about injuries with emojis that hinted he is struggling with one. 

The now deleted post came after Ariel Helwani announced on Wednesday that the  Irishman's scheduled bout with Michael Chandler is in 'very much in limbo'.

'I continue to check in and be a pest and be annoying,' Helwani said of his coverage of the events. 'I found out, via multiple sources, that they are reaching out to people again. They are reaching out to managers. They are reaching out to fighters.' 

'I would say this fight is very much in limbo,' Helwani continued. 'I would say that it's hanging on. And I would say that the UFC is working very, very hard right now to figure out a plan b.'

So what does plan b look like? Here, Mail Sport takes a look at the current options. 

Prochazka vs Pereira 2

The former light-heavyweight champion has teased that he has signed a contract for an unknown fight.  

Prochazka was in attendance at OKTAGON 58 and said an announcement would be coming soon during a cageside interview.

'I would also like to announce that I have signed something, but we will have to wait,' he said. 'Because again my organisation is a bit late with it.'

'So, I hope that in a few days, we will know, and it will be out there, and we will go for it.' 

His interviewer then predicted that it will be the main event of UFC 303.

'I think Jiri Prochazka will be the injury replacement at UFC 303,' Ondrej Novotny said. For the injured Conor McGregor, in a title fight with [Alex] Pereira in the main event.'

Prochazka lost his title to Pereira in November with the  Brazilian winning via second round TKO.

Sean O'Malley

The least serious option on this list.

As skepticism over the Irishman's first fight in nearly three years circulated, Sean O'Malley took to Twitter to throw his hat in the ring.

O'Malley posted on social media that he would 'fight @jakepaul to save UFC 303'.

YouTuber turned boxer Paul has become one of the bigger names in combat sports but there is little to no chance of him stepping in the cage.

However, it could be a sign that O'Malley could be persuaded to fight on June 30.

The American has drawn comparisons with McGregor throughout his rapid rise and would be the  marquee name the card needs.. 

Max Holloway 

Chandler has already waited an incredibly long time for the UFC's biggest 'money fight' and you'd imagine he'd be willing to wait a little while longer.

However, the prospect of a piece of a belt may be enough to keep him on the card.

A bout with reigning BMF champion Max Holloway looks to be the best bet in terms of keeping star power at the top of the card and it would certainly be one fans would get excited for.

Holloway is coming off the back of an all-time great knockout of Justin Gaethje and is no stranger to stepping in at short notice. 

Alexander Volkanovski

Another man with history of saving an event and the former featherwight champion says he'd be willing to do it again.

Asked if he'd be willing to step in as a replacement, Volanovski told Submission Radio: 'yeah, I reckon 100%.

As long as it's a big fight. I won't just take any fight. Like you said, that's a big deal. Save the day as well, I don't know, I feel like I just love saving the day. I'm just that good of a guy. If I have to save the day, I'll save the day.

'Obviously, get paid well for it as well. But you never know. I just was muckin' around with that. I don't even know if - probably nothing even happened. 

'It's probably just a little hiccups and everyone's blowing it out of proportion, but I'll have fun and throw the name out there just for a bit of a laugh.'

The Australian has been knocked out in his last two bouts but a throw down with Chandler still has the makings of a fun fight.