"Darron's a special footballer. What he brings to the team is quite unique and I think he is one of those players that is at the perfect moment of his career," the Spaniard told evertontv.
"He's ready to take a big role at Everton. To miss any player at this stage of the season would be a real blow.
"He has been working over 60 to 70 hours, and then if we lose him a few days before the start of the season it would be a big disappointment, but we hope that Darron can recover very quickly."
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