Mexico boxing legend Julio Cesar Chavez gave his goodbye to Los Angeles Saturday night, scoring an easy unanimous decision over one-time contender Ivan Robinson at the Staples Center. The 42-year-old Chavez dominated the action from the start. Robinson went down in round four and lost one point in round eight for spitting out his mouthpiece. When it was over, Chavez won by scores of 100-88, and 99-89 twice. Chavez, from Culiacan, Mexico, had fought only four times over the past four years. Robinson, meanwhile, is just 3-7-2 in his last 12 fights. On the undercard, Chavez' son, Julio Jr., scored a first-round knockout of Adam Wynant. The younger Chavez needed just 42 seconds to dispatch his foe. The elder Chavez ran his record to 108 wins, five defeats and two draws, with 87 knockouts. His 19-year-old son, meanwhile, saw his mark climb to 19-0 with 14 knockouts. Robinson, 34, fell to 32-10-2, with 12 knockouts. Also on the card was a 12-round IBF bantamweight title match between champion Rafael Marquez of Mexico City and Ricardo Vargas of Tijuana, Mexico. Marquez won rather easily to run his record to 34-3 with 30 knockouts. Marquez won by scores of 118-109, and 116-111, twice. Mexican flyweight Ruben Contreras, who was fighting on the undercard, had to retire after six rounds in his fight with Brian Viloria. Shortly after the bout, Contreras suffered a seizure and was rushed to the hospital to stop bleeding in his brain. The 32-year-old's prognosis has yet to be determined. Contreras' record is 9-17-3, while Viloria is 17-0 with 10 knockouts.