Greece coach Otto Rehhagel admitted Wednesday's 2-0 defeat to Paraguay was a learning experience as he shapes his side for the World Cup opener against South Korea.

The Euro 2004 champions went down to early goals from Enrique Vera and Lucas Barrios, a further setback in their build-up after they could only draw 2-2 with North Korea last Tuesday.

Rehhagel said: "For the first 15 minutes we were asleep, we conceded two goals and it was difficult to recover. After 25 minutes we woke up and got into the game. I took meaningful conclusions from this game, especially regarding the team to play South Korea."