Roberto Martinez says he will give captain Phil Jagielka every chance to prove his fitness ahead of Everton's FA Cup quarter-final at Arsenal.
The Blues skipper is a major doubt for Saturday's clash at Emirates Stadium, having missed last weekend's victory over West Ham United with a hamstring injury.
Martinez admits the initial prognosis would make the visit of Cardiff City on 15 March a more likely target for Jagielka - but says he would never rule out the defender from making a quicker-than-expected recovery.
Jagielka made a speedy comeback from a similar muscle problem in January and Martinez told evertontv: "With Phil, you can never rule him out. From a medical point of view, he should be missing the game against Arsenal - I was probably looking more at the Cardiff game.
"But knowing him and how he's reacted to this similar injury that he's had in the past, he could heal a lot quicker.
"I'm not going to rule him out and we're going to give him as much time as he needs to make a final decision."
Jagielka's injury has prevented him from joining up with the England squad due to play Denmark on Wednesday and Martinez added: "In a way it's good that he's behind-the-scenes here at Finch Farm and he hasn't got the game with the national team.
"That could give him a small percentage to be fit for the weekend. We'll see how this week unfolds and make a final decision closer to the game."
The Spaniard also confirmed he has no fresh injury concerns following the win over West Ham.
He said: "There are no new knocks. Everyone else is fit and we're hopeful everyone will come back from their international games fit and ready to go."
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