England centre-back Phil Jagielka has revealed he has yet to recapture full match sharpness, with the World Cup little over two weeks away.
The Everton defender was selected in Roy Hodgson's provisional 30-man squad and is expected to partner Chelsea's Gary Cahill, despite having played just two Premier League matches since February.
England face Peru on Friday, before two further pre-tournament friendlies against Peru and Honduras, and Jagielka admits the games will be vital for him.
Roy Hodgson has taken his England side to the Algarve in Portugal for warm weather training, with the players wearing three layers of clothing to prepare them for the heat intensity of Brazil.
And Jagielka told the media that he has found it hard to cope on the back of injury problems during the 2013-14 campaign.
He said: "Warm-weather training last week was a little bit difficult, and it will be difficult this week but it is something I need.
"I do not feel 100% fit but I do feel really good at the moment."
Hodgson picked Manchester United's Chris Smalling and Phil Jones as other alternatives at centre-back for the World Cup, however Jones has been struggling with a shoulder injury.
The youngster suffered the injury in a club fixture against Hull earlier this month, but is expected to be fit after taking part in ball-work training for the first time on Tuesday.
Uncapped teenager John Stones is the back-up centre-back should there be any drop-outs.
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