As Rocky Fielding recalls, it was a Wednesday night when his trainer, Jamie Moore, called to let him know they had an opponent lined up for the first defence of his WBA 'regular' super-middleweight title.

Moore only had to mention one word to let the champion know it was an opportunity simply too good to turn down – Canelo.

Saul Alvarez, one of the superstars of the sport, was last seen ending middleweight rival Gennady Golovkin’s unbeaten record, a result that created waves of attention across the world.

Now the Mexican – a two-weight world champion and a huge box-office draw – had his sights set on a relatively unknown 31-year-old who had appeared stuck in boxing purgatory just six months earlier.

Fielding's name may have barley made a ripple across the pond from his home in the north west of England before the bout was confirmed, but on Saturday he gets the chance to make a huge splash.

"It's a win-win for me," he told Omnisport during the press tour in New York to promote the fight.

"I'm fighting the biggest star in boxing and headlining at Madison Square Garden. Anyone would be stupid to say, 'no, I'll leave that and go and fight on the undercards at the O2 [Arena] or the Echo Arena'."

Fielding knows all about fighting on undercards, too.

In March, he was a supporting act in Sheffield, beating Karel Horejsek on points in an eight-rounder that served no other purpose than to stay active.

He continued to train, albeit with no clear purpose. Already British and Commonwealth champion, Fielding patiently had to wait for a world-title shot to come his way.

That opportunity finally arrived in July. Despite receiving just five weeks' notice, he produced a performance against WBA champion Tyron Zeuge in Offenburg, Germany, which dramatically changed his career path. From seemingly going nowhere he suddenly held a title, courtesy of a sensational fifth-round stoppage victory against the odds.

"There was a time before I fought for the world title where I had six months in the gym and didn’t know what was going on," Fielding recalled.

"I got that call five weeks before the Zeuge fight to go for a world title and I took it. That's what boxing is about – when you get that opportunity, you've got to take it.

"It made up for the six months in the gym with no date, not knowing what was going on. I was a bit down, but that's well gone now."

Few gave Fielding much hope of pulling off an upset on German soil. Even less now believe he can become just the second man to defeat Canelo, following in the footsteps of the legendary Floyd Mayweather.

The underdog is not concerned by opinions, though.

"I'm in boxing to challenge myself – and this is a big challenge. But it's one I'm looking forward to and confident about," he said.