Who is Andre Berto?

Berto (22-0) hopes to put that question to rest Saturday night when he defends his title for the first time against Steve Forbes. While most fighters see their stock rise after capturing one of the four (WBC, IBF, WBA, WBO) accepted titles, the 25-year-old Berto has been stuck in neutral since claiming the Mayweather's vacated title last year with a seventh-round TKO win over Miguel Rodriguez this past June.

While Antonio Margarito, Miguel Cotto, Paul Williams, Joshua Clottey and Shane Mosley circle each other, Berto has flown under the radar. The 2004 Olympian has been dropping opponents at a staggering clip (19 of his 22 wins have come by knockout) while getting his boxing education on the fly. After being knocked down for the first time in July of '07 by an uppercut from Cosme Rivera, Berto returned two months later to knock out David Estrada in a career-high 11 rounds.

"The Rivera fight taught me never to take anyone for granted," Berto told SI.com. "And after Estrada I went to work on my defense."

Berto faces a new challenge in the crafty Forbes, a defensive-minded fighter who has never been knocked out. While Berto says he will continue to look for the power shots, he says he is mentally prepared to go 12 rounds with the former super featherweight champ.

"I'm in ridiculous shape," Berto said. "All camp I've been trying to tire myself out, but I can't do it."

A win would go a long way toward inserting Berto's name into the welterweight mix, or at the very least, making one of the more high-profile contenders target his belt.

"I'm a risky fight for them," Berto said. "If they [lose], it would be a big step back. I don't blame them for not wanting to fight me. But in due time, they are going to have to.