By Jake Donovan

It’s the biggest fight of Marcos ‘Chino’ Maidana’s career, as the Argentine puncher heads into Las Vegas as an 11-1 underdog to unseat Floyd Mayweather, the very best fighter in the world.

The odds alone suggest a mismatch, and an insurmountable task. The early predictions among those in the media also suggest that Maidana doesn’t stand a chance in Saturday’s SHOWTIME Pay-Per-View headliner.

All of this would bother Maidana, except that he’s been here before and, on several occasions, has overcome the odds to produce some of the best moments of his career.

“It doesn't bother me at all,” Maidana says of the majority of the industry leaning towards his opponent in terms of picking a winner for this weekend’s big event. “All I've got to say for people doubting me is to and order the fight because they're going to enjoy a good fight. They're going to see me beat Floyd Mayweather.”

It seems as if Maidana (35-3, 31KO) is never meant to win a big fight, yet here he stands – a titlist in two weight classes and among the top five or so welterweights in the world at present time.

The current lofty ranking comes as a result of his emphatic  12-round beatdown – and many will argue, exposing – of previously unbeaten Adrien Broner last December. Maidana was expected by most to serve as the stiffest challenge to date for the brash three-division titlist, but few if any expected him to win, never mind dominate in the manner in which he did.

Maidana proceeded with his business without a care in the world. A knockdown in round two proved to be a game changer. Maidana caught Broner clean, put him down and spent the rest of the night fighting the perfect fight. Broner spent the rest of the night trying to play catchup and too much of the bout – and the time leading up to fight night – not at all prepared for the incoming.

It wasn’t the first time Maidana shocked the world. If his team is to be believed, it won’t be the last and by Sunday, May 4 won’t even be the most recent occurrence.

“[T]he fact is that Floyd has never faced somebody with the power and the heart, the determination that Chino has,” insists head trainer Robert Garcia. “This is a fighter who doesn't worry about anything. He's not worrying about, ‘I'm fighting the best pound-for-pound in the world or the best fighter in history.’ He's not worried about that. He gets ready to fight and do what he does best and he does it against anybody.

“It doesn't have to be the best in the world. He goes out there just to try to hurt his opponent and that's what he's training to do. He throws punches from different angles. He has tremendous power in both hands. Everybody knows that. There is no secret to that. He doesn't respect whoever is in front of him. That's one thing that he's going in and not thinking of, or not having in mind, I'm not getting the vibe from him that, ‘I have no chance against him.’ No, he doesn't feel like that. He feels like he could beat him and anybody else in the ring in front of him.”

Broner was in the neighborhood of a 5-1 favorite to remain unbeaten in San Antonio last December. Victor Ortiz was considered to be as big of a betting favorite for their June ’09 clash, a night intended as Ortiz’ coronation. Maidana had only lost once to that point, a disputed decision landing in favor of Andreas Kotelnik, who was actually supposed to be Ortiz’ opponent that night but instead accepted a more lucrative opportunity to face – and eventually lose to – Amir Khan.

Maidana was more than happy to accept the assignment, which meant making his debut on a major American cable outlet with the fight carried by HBO. Not only did Maidana defy the odds that night, but overcame a boatload of adversity as he was dropped three times, only to score three knockdowns of his own before forcing Ortiz to quit inside of six rounds.

The win led to what at the time would serve as the two biggest (read: most lucrative) fights of his career. They would also provide suggestions of vulnerability, riding out an early knockdown to take Khan to hell and back in a Dec. ’10 loss that many hailed as that year’s best fight. Four months later, Maidana prevailed in another thriller, barely getting past a suddenly reborn former three-division champ in Erik Morales, who would go on to win a belt in a fourth weight class later that year.

At the time, it appeared to be the last great moment of Maidana’s career. A wide points loss to Devon Alexander in Feb. ’12 was momentarily dismissed as merely an ill-advised move by the Argentine puncher to move up to welterweight. At the same time, however, he had already suggested that his body was no longer capable of shrinking down to 140 lb., lending the suggestion that he – physically – he was suddenly a man without a country.

The loss to Alexander was enough to motivate Maidana to make sweeping career changes. It led him to Robert Garcia’s Boxing Academy in Oxnard, California. The two are 4-0 so far, including thrilling knockout wins over Jesus Soto Karass and Josesito Lopez, in addition to the landslide win over Broner.

None of those fights are as big as what he expects to encounter this weekend. However, all have helped him prepare for this moment, a fight card aptly named ‘The Moment.’

“This is the most important part of my career,” Maidana acknowledges. “The fight with Broner gave me a lot of exposure, but this fight itself is the biggest fight of my career.

“It would be a tremendous upset and that's what I'm training for, to upset the world and to do it for my country. It would be huge for my country.”

Jake Donovan is the Managing Editor of Boxingscene.com, as well as a member of Transnational Boxing Ratings Board and the Boxing Writers Association of America. Twitter: @JakeNDaBox