Everton have been rocked by the news that Stevan Pienaar is set to be sidelined for a month with a hamstring injury, reports the Daily Mail.
The creative midfielder picked up the injury in training last week, which led to him sitting out Saturday's 1-0 win over Chelsea.
The South African international is one of the most influential players at Goodison Park and his absence will be cause of great concern to new manager Roberto Martinez.
The lay-off means that Pienaar could miss as many as three Premier League fixtures, as well as one League Cup tie.
The Toffees will hope they don't get too many more injuries, as Darron Gibson and Antolin Alcaraz are also in the treatment room.
However, Martinez had been prepared for such events and strengthened his new squad over the summer. There is plenty of cover in Pienaar's department.
New signings James McCarthy and Gerard Deulofeu are capable of covering the position, as well as the likes of Kevin Mirallas and Leon Osman.
Blues fans will be fairly happy with their start to the season - they are currently unbeaten in ninth, although three of their four outings have ended in draws.
They face a difficult trip to Upton Park this weekend to take on Sam Allardyce's West Ham United, and Pienaar will have to watch from the sidelines.
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