Dwight Yorke has warned England that "everyone must play to their maximum" if Sven-Goran Eriksson's side are to lift the World Cup.

The Trinidad and Tobago skipper claimed England were "going through a testing time" after struggling to overcome Paraguay and the Soca Warriors in their opening two games.

David Beckham and Co were booed off at half-time by a section of fans before late goals from Peter Crouch and Steven Gerrard spared their blushes and secured a place in the last 16.

Yorke believes England have the quality to make a massive impact in Germany but all their players must be on top of their game for it to happen.

The former Manchester United star said: "It is a testing time for England.

"People are saying they are not displaying the kind of champagne football they expected and they are not winning in the kind of manner they want to see the players achieve.

"England are desperate to win the World Cup but actually performing and beating all the teams in the competition is going to be hard. They will have to be at their very best.

"There is no doubt they have the talent. You look through the squad and it's not just because of Wayne Rooney. Yes, he brings a different dimension to the team but there are fantastic players throughout.

"Everyone has to play to their maximum for England to achieve what they want to achieve. If they don't, they will probably fall short."

Rooney was brought on for the final 32 minutes against Trinidad and Tobago - his first action since returning from a broken metatarsal - and he came through with no ill effects.

But Yorke insists it will take time for the 20-year-old to regain full sharpness after a near seven week lay-off.

He said: "Wayne is not match fit and it will take time before he gets to that level.

"He is a massive player, a massive influence for the team. He is such a young man but such an important player.

"But, coming off such a bad injury, it takes time to get to where he was - and certainly he was in outstanding form before the injury happened.

"I am sure the quicker he gets him back to his real best, the more important it will be for England."

Trinidad and Tobago goalkeeper Shaka Hislop can see encouraging signs for England, who succeeded where Sweden had failed in breaking the determined resistance of the Caribbean side.

The West Ham player said: "Can England win World Cup? I don't know. Time will tell. But they've grown over the last two games.

"They had to show a lot of determination against a team who were determined not to lose and came into the tournament with nothing to lose.

"England can take some heart from the result. Everyone thought it was going to be a foregone conclusion and it was a matter of how many goals England would score.

"I wouldn't say we were insulted but we feel we are better than to be simply written off.

"Sweden did it at their peril and England came within seven minutes of finding themselves in a very similar situation."

Midfielder Chris Birchall said: "England will be criticised but they have played two games and won two without conceding a goal - on that basis you can't criticise them.

"They struggled to create clear-cut chances and people say they are bit one-dimensional with Peter Crouch up front.

"But Wayne Rooney is a great player who can inspire them. He was not at his best when he came on but it gave the country a lift.

"He's a special player. The fans know that and the rest of the country knows that."