Proving grounds: Robert Guerrero eager in face of biggest challenge to date

Robert Guerrero has spent the last three years or so chasing the biggest names in his division.

He was challenging the likes of Floyd Mayweather Jr., the world's finest boxer and a super welterweight title-holder, when he was still a lightweight.

Mostly, though, his cries have fallen on deaf ears. While he's sought the likes of Mayweather, Juan Manuel Marquez and Manny Pacquiao, he's gotten decidedly less sexy names like Joel Casamayor, Vicente Escobedo, Michael Katsidis and Selcuk Aydin.

"It's really tough to want to fight the best and not get a response," Guerrero said.

But that will change, in a way, when he meets Andre Berto on Saturday in the main event of an HBO-televised doubleheader at the Citizens Business Bank Arena in Ontario, Calif.

Berto isn't a particularly big draw – he failed to sell 1,000 tickets for a 2010 fight against Carlos Quintana in his hometown – but he is by far the finest opponent Guerrero has yet faced.

If Guerrero, who is 30-1-1 with 18 knockouts and hasn't lost in nearly seven years, is truly an elite welterweight, he's got the perfect opponent to prove it against.

"I love boxing, so every fight is appealing to me," Guerrero said. "But this is one that is going to push me over the hump. Berto has that big name and is considered by everyone one of the best fighters in the world. It's what I need to get me over the hump and it's really gotten me excited."

Guerrero has had titles at featherweight, super featherweight, lightweight and welterweight, though his lightweight and welterweight belts have been of the interim variety.

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Thus far, his opponents have been primarily second-tier fighters. He hasn't had that elite opponent in his prime who would provide definitive proof that Guerrero himself is elite and that his record is not simply the result of beating up on patsies or past-their-prime opponents.

Excluding Mayweather and Pacquiao, Berto is as good as it gets at welterweight these days. He has a combination of speed and power that Guerrero has yet to experience.

Guerrero gets that. He scored a one-sided victory over unbeaten but largely unknown and untested Selcuk Aydin in July in a bout most notable for Aydin's ability to take a punch.

"Aydin did come and take some punches, but he wasn't a punching bag," Guerrero said. "He was a punching wall. He's a tough guy, comes in strong, and he was determined to win. And the one thing that's hard to stop is a determined man. But Andre Berto ... is obviously a different fighter. He knows how to make fights."

Berto is 28-1 with 22 knockouts, his only loss coming to Victor Ortiz in a wild slugfest in 2011 in which both men were knocked down twice. By far, he'll represent the toughest challenge of Guerrero's career.

This has been a trying year for Berto, however. He was supposed to fight a rematch against Ortiz in June, but tested positive for the anabolic steroid nandrolone in May.

Berto claimed he was innocent and the California State Athletic Commission ultimately agreed with him, ruling his positive test result was due to inadvertent contamination.

It was cleared fairly quickly, but the accusations still took their toll, he said.

"This last year, it's been one of the hardest years I really had to go through," Berto said. "And like I said, it has definitely matured me just as a man, just to get ready for everything in your head. Just like they always say, it's always a storm before a blessing, man. And I went through a hell of a storm within this last year, and it does put me in perspective with a lot of different things, and I'm right here in the position just to move forward."

Guerrero wants to move forward, and if he beats Berto, he figures to be prominently in the mix for the kind of mega-bout he seeks. His affiliation with Golden Boy Promotions might make it difficult for him to land a bout with the Top Rank-handled Pacquiao or Marquez, but he clearly would have to be in the mix for a Mayweather bout.

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Golden Boy president Oscar De La Hoya suggested as much, which was all Guerrero needed to hear.

"I have great respect for Andre Berto and what he has accomplished, but I see this fight as a step on the way to a mega-fight," Guerrero said. "I have a lot of incentive to win because of that. Andre had the whole steroids thing and that set his career back, so I'm sure he wants to make amends.

"That's what makes a great fight. I want to take the best fights and fight the best fighters and give the sport and the fans what they want. I don't know what Andre is planning, but I know I'm going to come out there with the intention of putting on a show for the fans. And hopefully, that will be the step in the direction I need to get those kind of big fights."

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