Online sportsbooks have established world champions Ivan Calderon and Rocky Martinez as favorites to retain their titles on Saturday night at the Coliseo de Puerto Rico José Miguel Agrelot in San Juan, Puerto Rico. Unbeaten WBO junior flyweight champion Ivan Calderon (32-0-1, 6 KOs) is a -550 pick to defeat challenger Rodel Mayol (25-3-1, 19 KOs) in their rematch of the June 13 technical draw. Mayol backers can get +350. In the other world title fight on the card, unbeaten WBO junior lightweight champion Rocky Martinez (22-0-1, 13 KOs) is heavily favored to dispose of Vicente Martin Rodriguez (25-2-1, 13 KOs). Martinez is -1300 while Rodriguez is +700. The card will be transmitted on Pay Per View at $29.95 for all of the cable systems (IN Demand) and by DIRECTV.