(CNN) -- China's star hurdler Liu Xiang bounced back from his Olympic Games disappointment to claim his third successive Asian Games gold medal, but Wednesday's action was marred by a second positive drug test by a Uzbekistani athlete.
Liu limped out before his first 110-meters hurdles heat in Beijing two years ago, but has since recovered from an Achilles injury and returned to form on home soil with victory in Guangzhou.
The 27-year-old headed off teammate Shi Dongpeng in a record time of 13.09 seconds in front of 80,000 people as he bettered the marks he set in winning in Qatar four years ago and South Korea in 2002.
"My coach always has confidence in me. I am confident of myself too. I am quite sure of my form," the former world record holder told the Xinhua news agency.
"The Asian Games is important to me, and after that I will focus on the preparation for the 2011 world championships as well as the 2012 London Olympics."
Shi clocked a season's best time of 13.38 while South Korea's Park Taek Yong claimed the bronze medal in 13.48.
China also won gold in the women's pole vault as Li Caixia claimed her first Asiad title from teammate Li Ling and Japan's Tomomi Abiko.
With three days of competition remaining, China leads with 173 gold medals and 352 in total -- beating its previous record of 342 in Beijing 20 years ago. The nation is also on target to beat its unprecedented 183 titles from that same year.
Xu Linyin and Wu Penggen won the men's beach volleyball, the women's hockey team triumphed over South Korea, and He Min earned gold in the men's 1m springboard diving and Wu Minxia in the women's event.
South Korea is second on 71 as Kim Deok Hyeon won the men's long jump to become the first male from the republic to win an athletics gold.
Japan has 36 golds after Tatsuhiro Yonemitsu's win in men's 66kg freestyle wrestling and Rika Usami's victory in women's karate's individual kata.
Iran moved up to fourth on 16 after Ehsan Hadadi won the men's discus and wrestler Jamal Mirzaei claimed victory in the men's 84kg freestyle division.
Uzbekistan is 11th on five golds after Yuliya Tarasova won the women's heptathlon, but wrestler Jakhongir Muminov followed judoka Shokir Muminov in testing positive for the banned stimulant methylhexaneamine.
Jakhongir failed an out-of-competition doping test on November 19, while Shokir -- who is not related -- lost his silver medal last Friday.
The duo joined a growing list of international athletes who have tested positive for the drug, which is generally used as a nasal decongestant.