Australia beat defending champion Iraq on Saturday to reach the Asian Cup semifinals for the first time, while South Korea downed Iran to move one step closer to its third title.

Both matches were scoreless until being decided in extra time. Harry Kewell headed in the winner with three minutes to go in extra time to give Australia a 1-0 victory that avenged a loss to Iraq in the 2007 group stage.

South Korea also kept its fans waiting, with substitute midfielder Yoon Bit-garam scoring with a left-foot drive from just outside the area in the 105th minute for a 1-0 win.

Australia will play Uzbekistan Tuesday and South Korea faces archrival Japan.

Australia and Iraq appeared to be heading for penalties when Matt McKay's cross found a streaking Kewell, who headed it past Iraq goalkeeper Mohammed Kassid in the 117th minute. Kewell, who plays for Galatasaray in Turkey, stripped off his jersey and swung it around in celebration after scoring his 15th international goal and second of the tournament.

"I am very pleased and happy with the team's performance today," Australia coach Holger Osieck said. "We managed to qualify for the semifinals which is definitely a great achievement."

Iraq coach Wolfgang Sidka felt his team was competitive throughout the match.

"You know, it was a very exciting match for both sides," he said. "It was up and down. You saw everything in this game. We always played in front and tried to create chances especially in extra time, in the last 30 minutes. In the end, it was one cross and one header."

In the late game, three-time Asian Cup champion Iran seemed to have the edge going into extra time, but it was the South Koreans who started attacking the Iranian net.

The breakthrough came in the 105th minute when Yoon received the ball from midfielder Lee Chung-yong. He shifted to his left past two defenders and then drilled a left-footed shot from the edge of the penalty box for the winner.

In the second period of extra time, Iran tried desperately to find space but South Korea crowded its defense and hung on to win. The closest Iran came to tying the match was a shot from Masoud Shoajei with six minutes left in extra time that hit the top of the net.