Chinese boxer Hu Qing and Silamu Halati beat their respective rivals on Saturday to qualify for the semifinals at the Asian Games in Doha on Saturday.
Hu took command with short-range blows at the first bout and went ahead 28-8 at the third when his opponent, Asylbek Talasbaev of Kyrgyzstan, was announced defeated.
"I am quicker. I used my sudden attacks and kept the distance between us so his punches could not reach me," said Hu.
Following Hu, Silamu Halati became the fifth Chinese medalist in boxing with an impressive 49-26 win over Behzobek Yunusov of Uzbekistan.
"We two have quite similar styles but I was faster than him," said Halati, referring to his rival who took a standing eight count at the final bout after a heavy punch landing on his face.
Two upsets happened on boxing giants Kazakhstan and Uzbekistan on Saturday.
Utkirbek Haydarov, a Busan Asian Games champion in the middle weight, failed to clinch a bronze for Uzbekistan in Doha. He was defeated 31-18 on points by Iranian Mehdi Ghorbani who said he was eager to get a gold for his country.
Kazakhstan's 81kg-category boxer Yerdos Janabergenov, the world champion, also lost to Tajikistan's Djakhon Kurbanov 33-21 on points.
Angkhan Chomphuphu, Thailand's 2002 Busan Asian Games -65kg wushu champion, continued his winning run in boxing after a 29-21 win over his tough challenger Sherali Mamdaliev of Tajikistan.