LAS VEGAS (AFP) - Japans Toshiaki Nishioka successfully defended his WBC super bantamweight title, unanimously outpointing Rafael Marquez at the MGM Grand hotel and casino on Saturday. The 35-year-old Nishioka boosted his record to 39-4-3 in his seventh title defence and first on US soil. He received winning scores of 117-111, 116-112 and 115-113 from the three ringside judges. Marquezs record fell to 40-7. Nishioka has won 16 fights in a row, 10 of them by knockout, since last losing in 2004 to Thai legend Veeraphol Sahaprom. The Las Vegas showdown was the seventh title defence for the southpaw since he took the crown from Thailands Napapol Sor Rungvisai in 2008 at Yokohama. Nishioka said recently he wants to fight Filipino star Nonito Donaire and then possibly retire. Donaire, 26-1 with 18 knockouts, has not lost in 25 fights over more than a decade entering an October 22 World Boxing Council bantamweight title defence in New York against Argentine southpaw Omar Andres Navarez. Donaire won a world crown in his third different weight class in February, taking his current crown with a second-round stoppage of Mexicos Fernando Montiel. On the undercard, Nicaraguas Roman Gonzalez remained unbeaten and retained his WBA title with an impressive second-round knockout of Mexicos Omar Soto. Gonzalez took control in the first round and 36 seconds into the second he sent Soto to the floor with a right followed by an uppercut. Soto fell to 22-9-1.