"The heat knocked us a little bit. It was the first time we'd faced temperatures like it was today," Eriksson told a press conference after the game.

England went on to win the game 1-0, courtesy of a 3rd minute own goal from Paraguay captain Carlos Gamarra, and Eriksson acknowledged that his team will have to do better.

"I know that to win the World Cup we have to play better football, but we will play better football," the Swede said..

"I'm sure we will play better and better every game. I think it was very important to get the three points."

Eriksson defended substituting Michael Owen with Stuart Downing in the second-half.

"I wanted to see some fresh legs on the pitch," he said. "I wanted Joe Cole as a link between Peter Crouch and the midfield.

We tried to have five in midfield and only Crouch up front and it got better in the end. I think Michael Owen did well and will get better and better."

Paraguay coach Anibal Ruiz doled out praise to the English team but said that his players were a match for the tournament favorites.

"We have to accept that we were up against a very hard team with great some individuals," he said.

"They are a good side and we were at their level, although we could have done more in the second half."

"After the surprise of the early goal, I think we managed to control a very strong team who could go all the way to the final," Ruiz added.

Ruiz said that the early goal that Paraguay conceded took his players by surprise.

"It took us a while to get into the game but after the surprise of the early goal we managed to control the English team and I think we could have done better in the second half," Ruiz said after the game.

The Uruguayan coach said that he is confident his team will improve in the coming games.

"In general terms we are quiet happy with what the team had done today and I'm sure we're capable of getting two good results in the next games," Ruiz said.