American bantamweight Diaz wins first bout

United States bantamweight boxer Joseph Diaz Jr. won his opening bout Saturday at the London Olympics.

The 19-year-old Diaz, competing in the 56-kilogram weight class, earned a 19-9 victory in his match against the Ukraine's Pavlo Ishchenko. It was the first match of the Olympic boxing competition.

Diaz was leading Ishchenko by a 9-6 margin after two rounds, then clinched his victory by outpointing his opponent by a 10-3 score in the third and final round.

The two-time reigning U.S. champion at bantamweight, Diaz moved on to the round of 16. He will next fight Wednesday against Cuban Lazaro Alvarez Estrada, who is one of the favorites to win gold. Alvarez is the world No. 2 and received a bye in the competition.

Tajikistan's Anvar Yunusov, the world No. 1, Great Britain's Luke Campbell and Azerbaijan's Magomed Abdulhamidov also got byes into the second round.

The first round of the men's 75kg (middleweight) competition also took place Saturday, and Great Britain's Anthony Ogogo was a 13-6 winner against Junior Castillo Martinez of the Dominican Republic.

Ogogo's next opponent will be a tough one -- top-seeded Ievgen Khytrov of the Ukraine. Khytrov won the world championship in 2011.

He, along with Japan's Ryota Murata, Romanian Bogdan Juratoni and Brazilian Esquiva Florentino, received byes into the second round.

Among other middleweight bouts, two-time world titlist Abbos Atoev of Uzbekistan moved on, as did 2008 bronze medalist Vijender Singh and American Terrell Gausha.