As is becoming something of a tradition at the continental championship, the two sides met at the quarter-final stage for the fifth straight edition and once again the game proved a closely-fought affair.

Neither side could break the deadlock inside 90 minutes but substitute Yoon Bit-garam ensured penalties would not be needed when he struck from the edge of the area in the last seconds of the first period of extra time to send the Koreans through to the last eight.

Manchester United midfielder Park Ji-sung was a strong presence for the east Asians in the middle of the park, where Iran struggled to impose themselves, and Cho believes it was in midfield where South Korea won the game.

"Iran are a good team and have had good performances in each game," said Cho.

"But the main reason we won this is because we controlled midfield. We did not let them play their own game.

"All the players have worked really hard in all four games to show the possibilities of Korean football and the changes we are trying to implement. They have a strong will to make things happen."

Next up for South Korea is an enticing clash with regional rivals Japan, who have looked stronger with every game at the tournament.

And, although Cho acknowledged it will not be an easy game, he insisted Alberto Zaccheroni's side hold no fear for him.

"The next match against Japan is one of the most crucial matches we are going to play," he said. "I agree that Japan have been getting better and better throughout the tournament in every aspect of their game.

"But I never get scared about the Japanese team, even when I was a player and as a coach, so I am not afraid of them."

Iran coach Afshin Ghotbi had talked up his side's chances of winning the Asian Cup in the build-up to the tournament and, although they have fallen short of achieving his target, the 46-year-old was proud of the efforts of his players.

"The potential of Iranian football is massive," said Ghotbi, who steps down to take charge of Japanese side Shimizu S-Pulse.

"The players have tremendous intelligence and qualities. If they are given the right education and support they can play with the best in the world.

"I feel they pushed South Korea to the limit and I am very proud of this team, and I have a positive feeling about the future of these players."