South Korea beat Colombia in a penalty shootout at the Under-20 World Cup on Wednesday to join Ghana, Chile and Iraq in the quarterfinals.

Having played out a 1-1 draw after extra time, Colombia was trailing 8-7 in the shootout when defender Daivy Balanta sent the last penalty over the crossbar.

South Korea will now play Iraq, which needed extra time to beat Paraguay 1-0.

Ghana and Chile will meet in the quarterfinals after both teams won their last-16 matches over 90 minutes earlier in the day. Ghana came from a goal down to beat Portugal 3-2 while two late goals earned the Chileans a 2-0 victory over Croatia.

Balanta's spot-kick wasn't the only one that failed to find the net. Earlier in the series, Song Ju-hun missed for South Korea while Felipe Aguilar saw his attempt saved by goalkeeper Lee Chang-geun.

Song had given South Korea the lead in the 16th minute when he beat goalkeeper Cristian Bonilla with a low shot after the Colombia defense failed to clear from the area.

Colombia pressed long for an equalizer and had to wait until the fourth minute of injury time before captain Juan Quintero scored with a fierce free kick that beat Lee at the near post.

The penalty shootout soon became inevitable as neither side was willing to take any risks by pushing forward in extra time.

It was different story in the other late game, though, after Iraq and Paraguay has finished 0-0 after 90 minutes, with the South Americans having been reduced to 10 men in the 80th. Iraq substitute Farhan Shakor scored the only goal with a firm header past goalkeeper Diego Morel in the fourth minute of extra time.

Paraguay, which defeated Argentina in qualifying, was without suspended captain Gustavo Gomez. It also lost Arnaldo Sanabria, who was booked in the 70th and sent off after another foul 10 minutes later.

Iraq continued a remarkable run in its first appearance in the tournament for 12 years. It won Group E, where it drew 2-2 with England, and will now play in the quarterfinals for the second time _ having also reached the last eight in 1989.

Earlier, substitute Yiadom Boakye set up the equalizer and then scored a late winner as Ghana rallied to beat Portugal.

Ghana was 2-1 down when Boakye came on the 75th. Four minutes later, Portugal goalkeeper Jose Sa saved his shot but allowed Michael Anaba to pounce on the rebound for the equalizer. Boakye then followed up by sending a free kick through the two-man wall in the 85th.

Kennedy Ashia had put Ghana ahead with a 25-meter (yard) effort in the 19th minute. However, defenders Tiago Ferreira and Edgar both scored within the space of three minutes to put Portugal 2-1 up in the 73rd.

Ghana was the last team to qualify for the knockout stage, after losing two group matches and narrowly advancing on goal difference following a 4-1 defeat of the United States.

Portugal, the 2011 runner-up, had scored the most goals in the group stage but failed to convert two early chances. Aladje was left unmarked but sent his effort over the crossbar after 15 seconds while Bruma, who scored five times in three group matches, shot wide a minute later.

Portugal dominated possession but ultimately paid the price for failing to make it count.

Chile similarly controlled large parts of its match against Croatia, which has never gone beyond the round of 16, but created few chances.

Nicolas Castillo finally broke the deadlock when he was set up by Sebastian Martinez and headed the ball backward over Croatia goalkeeper Oliver Zelenika in the 81st. Four minutes later, Croatia defender Jozo Simunovic sent a Christian Bravo cross past his own goalkeeper.

Chile finished third in 2007 but failed to qualify for the next two editions.

The other two quarterfinals are France vs. Uzbekistan and Uruguay vs. Spain. (AP)