GUANGZHOU, China (AFP) - Keigi Higashi's 45th-minute goal gave Japan a 1-0 win over Thailand and a spot in the Asian Games semi-finals on Friday where they were joined by fellow regional power South Korea.
The 20-year-old Higashi struck just before half-time, slotting the ball home from close range and past goalkeeper Samuel Cunningham.
Japan, top scorers in the tournament with 14 goals, will now face four-time champions Iran, who defeated Oman 1-0.
"Thailand controlled the ball well, but we controlled the match," said Japan coach Takashi Sekizuka.
"It was a tough match and we were lucky to score in the first half and we were able to defend in the second."
Thailand, coached by former England skipper Bryan Robson, created most of the pressure in the quarter-final clash but were unable to find the finishing touch.
"It's unfortunate. We were the better team over the 90 minutes," said former Manchester United captain Robson.
"We passed the ball well and got into good positions, but couldn't convert any of our chances."
South Korea were forced to extra-time before seeing off 10-man Uzbekistan 3-1 in their quarter-final and will now tackle the United Arab Emirates for a place in the gold medal match.
Hong Jeong-Ho put South Korea in front after just two minutes, but Sherzodbek Karimov pounced on a mistake by left-back Shin Kwang-Hoon in the 71st minute to equalise.
Uzbekistan played the last 30 minutes of the game with 10 men after star striker Ivan Nagaev was sent-off.
Monaco's Park Chu-Young, with his third goal of the tournament, restored his team's advantage in the second minute of extra-time with a smart twist and drive which goalkeeper Timur Juraev allowed to squeeze beneath his body.
Kim Bo-Kyung added the third in the 101st minute for an attack-minded South Korean team who peppered the target with 22 shots.
South Korea coach Hong Myung-Bo praised the influence of Park Chu-Young.
"He is an experienced player and leads by example. With him in our team we know what we are capable of," he said.
The UAE defeated North Korea 9-8 in a penalty shootout after the two sides had battled to a 0-0 draw after extra-time.
Ri Chol-Myong had his penalty kick saved by Ali Housani in the UAE goal before Mohamed Al Shehhi tucked away his spotkick to send the Gulf side into the semi-finals.
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