Losses to Ricky Hatton (left) and Shane Mosley derailed what was once a promising career for Luis Collazo (right), here trading punches with Hatton in their very close fight in 2006. Saturday's shot at titleholder Andre Berto might be Collazo's last chance to get back on track. Photo / Mr. Will-hoganphotos.com

Luis Collazo is in danger of becoming that unfortunate fighter who is loaded with talent but isn’t quite able to make it big. He admits it.

The soft-spoken southpaw from New York won a world title in 2005 but has had a string of bad luck since. Now, he is being called Andre Berto’s “toughest test to date,” a way of describing a fighter who is expected to lose but put up a good fight.

That’s why his shot at the unbeaten WBC welterweight titleholder on Saturday in Biloxi, Miss., on HBO is so crucial for him. If he loses, his dream of becoming a star might be dashed permanently.

“Definitely,” he said. “Every time, it seems, something has gone wrong. If I’m destined to be a superstar, it’s going to have to happen on Saturday. I’m going to leave everything on the table that night.

“This is it for me.”

Collazo (29-3, with 14 knockouts) blossomed in 2005.

That April, he was given only a few weeks notice yet whipped himself into shape and narrowly outpointed then-titleholder Jose Antonio Rivera to win the WBA welterweight belt. Four months later, he knocked out Miguel Angel Gonazlez in eight rounds in the first defense of his title. His future looked bright.

“It was a great year,” he said.

And then things turned sour. In his second title defense, he faced Ricky Hatton in Boston and lost a unanimous, but close decision – 115-112, 115-112, 114-113 – that many observers believed should’ve gone the other way.

Two fights later, in 2007, Collazo said he broke his hand in the second round against Shane Mosley in Las Vegas. He bravely survived for 12 rounds but was never in the fight and lost a one-sided decision.

The net result of the two setbacks: Hatton and Mosley are perceived as two of the best fighters in the world and earn seven figures when they work, while Collazo, at 27, struggles to rise to that level. He’ll earn only $150,000 on Saturday.

He wonders where he’d be had he won a few more rounds against Hatton.

“It bothered me for a couple of months,” said Collazo, referring that fight. “ÔǪ I know I’d get more recognition if I had won. I know I’d get bigger paydays and maybe be one of the top fighters pound-for-pound.

“That’s how it goes in boxing, though. You have to try to be a big person and do better the next time.”

Nirmal Lorick, Collazo’s longtime trainer and manager, believes the broken hand wasn’t his fighter’s only handicap in the Mosley fight.

“Had Luis won the Hatton fight, he might be making a million dollars,” Lorick said. “Is that hard swallow? Sure, it was for him. I think he had some depression leading into the fight against Mosley and that doesn’t help against a guy like that.

“For this fight, he’s focused again, back to when he won his title and fought Hatton.”

He had better be. Berto (23-0, 19 KOs) is one of the sport’s rising stars, a quick, gifted athlete whose punches are as explosive as anyone’s in the business.

No one expects Collazo, a tough, skillful fighter himself, to roll over and become just another victim. As Carl Moretti, matchmaker for Berto’s promoter Lou DiBella, put it with great passion: “If you don’t respect Luis Collazo, you’re not a real boxing person. We know this is a fight.”

At the same time, it’s difficult for many to imagine Collazo stopping Berto’s impressive run. One is soaring to toward stardom, the other hanging on, or so it seems.

Collazo is a heavy underdog among bettors even though he has solid credentials and Berto, according to many experts, has not faced a significant test in his four-plus-year career.

That’s fine with Collazo, who beat two journeymen after the Mosley fight to become Berto’s mandatory challenger. He knows there’s a sure-fire way to convince detractors: win on Saturday.

“I’ve always felt like the critics never gave me the respect I deserve as a fighter,” he said. “That motivates me. I love proving people wrong.”