The Koreans, who reached the semi-finals in 2002 as co-hosts, scored a goal in each half to deliver a strong message to their group rivals with a slick and confident performance to mark their eighth appearance in the finals.
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Lee Jung-soo and captain Park-Ji-sung netted early in each half to give South Korea only their second World Cup win on foreign soil and left Greece struggling to advance from a group that includes Nigeria and one of the favourites Argentina.
The Koreans defended solidly against the aerial threat of the Greek players, who bombarded them with lofted passes that yielded few chances for a country that has lost every game they have played at the finals without scoring a goal.
The 2004 European champions were besieged by a torrent of South Korean attacks, with the energetic European-based duo Cha Du-ri and Park Chu-young outrunning their opponents and proving a handful for the Greek defence.
"We played to win and our players worked really hard," said South Korea coach Huh Jung-moo, the first Korean to manage a World Cup side since 1998. "The team played well and the flow of the game was very good," he said.
FIT KOREANS
South Korea have dominated the Asian game and arrived in South Africa determined to reverse their mediocre World Cup form with a team built around their more experienced players based in Germany, England, Russia, France and Scotland.
Greece coach Otto Rehhagel had on Friday warned his players they would pay for slip-up against a team with abounding fitness and counter-attacking intentions.
"In the second half we made two huge mistakes," he said. "I knew the Koreans would be very fast, very swift and they would run the extra mile to get the ball. It was a well-deserved win."
Greece started brightly and could have scored in the third minute when Vassilis Torosidis steered Giorgos Karagounis's corner past the post with the Korean defence all at sea.
But South Korea, unbeaten in qualifying, looked dangerous and punished Greece with quick breaks and neat passing play that left their opponents outnumbered at the back.
They snatched the lead in the seventh minute when Lee Young-pyo's corner drifted past four defenders into the path of Lee Jung-soo, who volleyed the ball into the net to spark frenzied celebrations from thousands of travelling Korean fans.
Park Chu-young looked certain to double their lead near the half-hour mark when Park Ji-sung's incisive pass put him clean through on goal, only for his shot to clip goalkeeper Alexandros Tzorvas and spiral over the bar.
Park Ji-sung, uncharacteristically quiet in the first half, burst into life after the break and doubled South Korea's lead in the 52nd minute to deal a killer blow to Greece.
He chased a poorly weighted square ball from Avraam Papadopoulos, eluded two defenders and coolly slotted the ball
