Jorge Rubio's CV includes working with the Cuban national boxing team prior to his defection to Miami in 1996, and assisting in the training of former world middleweight champion Jermain Taylor for his first 11 bouts. He has also trained Zahir Raheem, an American lightweight who dropped a points decision in a challenge for the World Boxing Organisation (WBO) lightweight title in 2006, and former World Boxing Association (WBA) cruiserweight titleholder Robert Daniels, whose best days were more than 15 years ago.

His appointment last month as Amir Khan’s trainer took many people by surprise.

“I may not be known by a lot of people but I am confident about my ability,” Rubio said ahead of Khan’s 19th fight against unbeaten Colombian Breidis Prescott on Saturday at the MEN Arena in Manchester. “I worked with David Haye’s team, helping him to prepare for five fights before he won the world cruiserweight title. I want to do the same with Amir and I am convinced that he will also be world champion.”

Some observers are sceptical about Khan’s long-term prospects, particularly in light of the knockdown he suffered against Michael Gomez and the number of punches he sustained before he stopped the Manchester-based Irishman in the fifth round.

This was the third time that the 21-year-old Khan has hit the canvas in his professional career. Rachid Drilzane, a French journeyman who had lost three times, floored him in December 2006 (although Khan maintains that his feet got entangled in the ropes) and Willie Limond knocked him down in the sixth round in July last year. The 29-year-old Scot has accumulated only eight wins by stoppage in 31 contests and is regarded as a light puncher, while Drilzane had stopped no one in 13 bouts prior to encountering Khan. Gomez was five years removed from his last meaningful performance.

For Khan to compete at the top level, he will need to be more defensively sound than he was in June.

The unknown Rubio has plenty of work to do. “I know what Amir needs to do and the most important thing is that he keeps his hands up,” the Cuban emphasised. “He also needs to move his head more and work the jab. The potential is there, it is just a matter of putting in the time to learn.”

We will know soon if Khan has the instinct and hardness to survive. Prescott, 25, has stopped 17 of his 19 opponents but he is largely untested; all but two of his fights have taken place in Colombia.

This will be Khan’s first bout on Sky Box Office, so his pay-per-view pull will also be tested. “We delivered good ratings consistently for ITV,” said promoter Frank Warren. “Amir has a great fan base and this is the moment for him to move to pay-per-view.”

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