POMONA, Calif. – Golden Gate-based hotshot Sourdough Sam goes on the road Friday to Fairplex Park, where Southern California may discover what the fuss was about last year when Sourdough Sam emerged as the top 2-year-old in Northern California.“Last year he was a little bit unlucky, he should have been undefeated,” trainer Dean Pederson said. No complaints. Pederson and owner-breeder John Nicoletti are just happy Sourdough Sam is back for his second start after being sidelined eight months.Sourdough Sam, 4 for- 5 overall and impressive winner against older in his comeback, is the horse to beat Friday in the $50,000 Jim Kostoff Stakes, a seven-furlong sprint for 3-year-olds on the second day of the Los Angeles County Fair race meet.The nine entrants include 2009 California Cup Juvenile winner Bench the Judge, stakes-placed Pico Pico, and front-runner Pinal. But if Sourdough Sam reproduces his Northern California form while racing for the first time Southern California, look out.“He’s a horse that gives you confidence,” Pedersen said. “He’s got a great attitude, and has always been very professional.”Sourdough Sam, a laid-back gelding by Decarchy, raced four times last fall at Golden Gate. He scored a dazzling six-length debut victory, won a fast allowance, finished second with a bad trip in a stakes, then won the $61,000 Gold Rush his first try around two turns on Dec. 12. Then reality hit.“He came out of that last race with tiny fractures in both shins,” Pederson said. No surgery was required, Sourdough Sam healed with the best remedy – time.He stayed at Pederson’s barn the duration of his recovery, and when Sourdough Sam got close to a race, the best option was a turf allowance against older at Santa Rosa. Ridden for the first time by Chad Schvaneveldt, Sourdough Sam was hopelessly buried turning for home, positioned next to last and 10 lengths off the lead.Then he exploded. The gelding found a seam, accelerated, burst to the front, and won geared down. “That was wild,” Pedersen said.“We’re coming back a smidge quick off his layoff [less than a month], but going from five-eighths to seven-eighths is a good progression for him,” Pedersen said. How good is he? “We’ll know about him after Friday.”