PHOENIX (AP) -- Two men on Monday pleaded not guilty to murder and other charges stemming from the beating death in Phoenix of a 17-year-old national champion boxer. Police say Alexis Urbina on Sept. 3 was found unconscious and covered in blood in his family's south Phoenix home. He died of his injures two days later. There was no obvious sign of forced entry into the house, but Urbina's family told police some of his boxing memorabilia was missing. Charges against 22-year-old Robert Chavez and 23-year-old Joseph Jessie Corrales include 1st degree murder, burglary and trafficking in stolen property. Urbina won the 141-pound Youth Men's Division at the USA Boxing National Championships in April at Spokane, Wash. His family says he had Olympic aspirations.