Chicago:Thailand's Suriya Prasathinphimai defeated Georgios Gazis of Greece in the preliminary round of the World Boxing Championships on Wednesday.
The two traded blows in the opening rounds, but Prasathinphimai pulled ahead early and finished off the second round with a powerful left hook to make the score 13-5.
By round three, the confident Prasathinphimai displayed footwork as he easily evaded Gazis's punches and won the bout 19-6.
Earlier, American Raynell Williams defeated French featherweight Khedafi Djelkhir.
Djelkhir started quickly, but his aggressive approach backfired and enabled Williams to take a 10-point lead in the first round. Djelkhir was clearly frustrated by the end of the fourth round and lost the match 28-18.
World champion runner-up Aleksey Shaydulin struggled to find his balance against Maduma-Nzungami Ghislain of Congo through the first two rounds, but finally prevailed in his preliminary round featherweight bout.
Shaydulin took an insurmountable lead in the third round, connecting with a barrage of point-scoring hits late in the round. He went on to dominate the fourth round as well, winning the match 26-11.
European featherweight champion Albert Selimov of Russia defeated Romania's Julian Gabriel Stan with a series of punishing blows in the first round.
Selimov hit Stan with five straight punches, sending the Romanian to the canvas where the referee stopped the bout.
In another featherweight contest, Uzbekistan's Behodirjon Sultonov traded a flurry of punches with Jesus Marcelo Andres Cuellar of Argentina, moving ahead late in the first round and prevailing 31-13.
Wednesday was the second day of competition at the World Boxing Championships in Chicago.
The top eight finishers in the light flyweight (48kg) to light heavyweight (81kg) divisions and the top four from the heavyweight and super heavyweight classes qualify for the Beijing Olympics.