“The club can confirm that it received a written transfer request from Darren Bent following yesterday’s Wear-Tyne derby match,” Sunderland said on its website, without elaborating.
No one at Aston Villa was available to comment.
Former Ipswich and Charlton player Bent, 26, joined Sunderland from Tottenham in 2009.
Sunderland is sixth in the league after drawing 1-1 against Newcastle yesterday thanks to a late goal by Asamoah Gyan. Aston Villa is 17th of the 20 teams after a 1-1 tie at Birmingham.
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