Spain coach Jose Antonio Camacho said luck played a big part in South Korea's penalty shoot-out victory.
Two debatable decisions appeared to have cost his side a place in the semi-finals.
Fernando Morientes had a goal ruled out after the assistant referee ruled that the ball had gone out of play, only for replays to reveal that the strike was legitimate.
And Luis Enrique was pulled back for a questionable offside as he was bearing down on the Korean goal.
"It was hard for us, the same thing has happened to other teams," said Camacho, hinting at the similar fate that befell Italy in the second round.
"I'm sorry we couldn't do any more. We have worked and battled and the others had more luck then we did.
"All I can do is congratulate my players."