Smith will have to wait for the biggest challenge of his careerCredit: Mark Robinson/Matchroom

Mundo was set for the biggest challenge of his career when the pair’s original date was set for August 19.

But the champion underwent surgery on his jaw after suffering from a bone infection that came as a result of dental work.

That meant the 38-year-old’s mandatory title defence was delayed and the two fighters will now meet at the start of the new year.

Beterbiev vs Smith: Date and how to follow

This 12-round unified world title fight will now take place on Saturday, January 13.

It is being held at the Videotron Center in Quebec City, Canada.

It will be streamed by Sky Sports Action in the UK.

Sky Go customers will be able to stream the action via their laptops or mobile devices, while non-Sky customers will be able to watch the action on NOW TV.

A one-day pass costs £11.99 or £34.99 per month.

talkSPORT will have all the build-up during fight week and talkSPORT.com will have all the reaction from Canada.

Beterbiev holds all three light-heavyweight beltsCredit: Top Rank

Beterbiev vs Smith: Undercard

Subject to change

• MAIN EVENT: Artur Beterbiev vs Callum Smith – for IBF, WBC and WBO light-heavyweight titles
• Jason Moloney vs Saul Sanchez – for WBO bantamweight title
• Christian Mbilli vs Rohan Murdock
• Imam Khataev vs Rodolfo Gomez Jr
• Christopher Guerrero vs Sergio Garcia Herrera
• Mehmet Unal vs Dragan Lepei
• Leila Beaudoin vs Elizabeth Chavez Espinoza
• Moreno Fendero vs Victor Hugo Flores
• Wilkens Mathieu vs TBA

Beterbiev vs Smith have a new date after the postponement

Beterbiev vs Smith: What has been said?

Betervbiev: “He’s good opponent. He’s good challenge for me.

“If we talk about my past opponents, I never say someone’s going to be easy for me, if it’s going to be easy for me or not.

“Like him too, I’m preparing for Callum Smith for 100 per cent like he prepare for me too.

“I have boxing coach and condition coach for power training, cardio.

“Every camp I ask them after sparrings or after my toughest trainings with my condition coach, ‘how is it? Is it better than five years ago or not good? How do you think?’ And they tell me it’s better than five years ago but I don’t know.

“I feel good too, but I think they lie to me. I feel good, I’m good. I feel everything good.”