Sunderland midfielder Andy Reid faces another month-long spell on the sidelines with a fresh hamstring injury.
Reid, who was out for four weeks after Christmas with a hamstring problem that saw him miss three games, sustained the latest blow in the 1-1 draw at Portsmouth eight days ago.
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"Unfortunately Andy has suffered a new hamstring injury," confirmed club physician Dr Glen Rae on the club's official website.
"He is working with the medical team, but is likely to be missing from training for around four weeks."
Reid could potentially miss Sunderland's next five Barclays Premier League games, starting at Arsenal on Saturday before matches with Fulham, Aston Villa, Bolton and Manchester City.
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