Paraguay coach Gerardo Martino revealed his side were in party mood following their historic victory over Japan tonight, although he admitted the full impact of their success has not yet sunk in.

Paraguay progressed to the quarter-finals of the World Cup for the first time after beating Japan 5-3 on penalties following a goalless draw in Pretoria.

The victory was reportedly greeted with a party atmosphere in the streets back in Paraguay, and Martino revealed his side were enjoying being part of those celebrations.

"Obviously we are having a party, we're celebrating together with the rest of the people of Paraguay," he said.

"I can imagine the happiness of the people there, and of course let them enjoy it.

"I've seen the players make a huge effort. It was a very close match and of course now we celebrate the fact we're in the quarter-finals."

Martino admitted it may take a while for their historic achievement to sink in.

"I believe that (goalkeeper Justo) Villar was right when he said in the dressing room that we haven't given the necessary importance to this match yet. Perhaps we will give it that afterwards," he added.

"It's the first time that Paraguay have made the quarter-finals and the same would've applied to Japan. I just think we were lucky during the penalties, that made the difference."

It was not the most exciting of matches, with clearcut chances at a premium during normal and extra-time.

However, Martino believes neither side should feel too disappointed about their performance.

"Perhaps it was not the way people wanted to see it, but neither the winner or loser have anything to reproach themselves about," he added.

Martino, who finished the match in tears, admitted it was an emotional success for him.

"There's a lot of fear, there's a lot of tension during a match," he explained.

"It's very difficult to go through a match like that, the extra time, penalty shoot-out, and everybody knows this is an unfair way to decide a match, but that's the way it is.

"Okay, we didn't play too well but I think we were looking for the win and we had some of the better moments on the pitch.

"But when you get all the way to the penalty shoot-out you make a huge effort and then the tension is released. So many things go through your mind, so there's the reason for the tears."

For Japan coach Takeshi Okada, it was a disappointing finale to what might have been his last game in the hotseat.

He also took responsibility for his side's exit.

Asked about his feelings when the winning penalty went in, Okada said: "To be honest I felt that our World Cup was over, so I felt really sad.

"In terms of how we played I have no regrets at all, the players were really wonderful and they've been truly proud of being Japanese and representing Asia. I'm proud of them.

"I couldn't make them win, that's my responsibility. I didn't get my emotion across and didn't make them eager enough. It wasn't enough on my part."

Asked about his future, Okada suggested his time as Japan coach may be coming to an end, adding: "In a state of not having any reflection, I don't think I have anything left to do now."