David Moyes has confirmed that centre-back Jarrod Branthwaite has sustained an injury and will be absent for Everton's season opener against Leeds United.
The defender sustained the problem during training as the Toffees continued their preparations for the upcoming campaign.
The Toffees begin their season away at United on Monday evening, but they will travel to West Yorkshire without the England international.
While Moyes declined to specify the duration of the defender's absence, he expressed annoyance that the information had been leaked earlier this week.
He said: "Jarrod picked up an injury in training so unfortunately we are going to miss him. These things happen.", reports the Liverpool Echo.
When questioned about Branthwaite's expected return timeframe, Moyes responded: "No and I wouldn't give it anyway, but I'm sure the insider inside the club will give that out, I'm sure of that. We have got to find out who is giving the news out."
He then added: "I'm unhappy [with the news being leaked out]. All managers don't like it. It is certainly coming from within our building and it is up to us to find out and we will do."
Vitalii Mykolenko was substituted during last weekend's loss to Roma, whilst Nathan Patterson and Harrison Armstrong were both unavailable for the fixture. When asked whether the trio might feature on Monday evening, Moyes replied: "We may have."
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