Sources: Philadelphia Eagles RB Brian Westbrook a free agent after 2010

Brian Westbrook's long-term security apparently isn't as long as he had anticipated.

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A revision in the five-year, $32 million extension the Philadelphia Eagles running back signed last August indicated the $7 million option bonus due in 2010 wasn't exercised by the team, according to multiple sources. By not exercising the $7 million bonus, Westbrook's contract ends in 2010.

The complicated extension, which reportedly was 60 pages long, had supercedes and bonuses, but it gave the team the right to trigger a clause that would extend the deal from 2011 to 2013. Under the new deal, Westbrook's base salary increased from $4 million to $5.85 million this season and goes to $7.25 million in 2010. His cap numbers increase to $13.25 million in 2009 and $10.59 million in 2010.

Westbrook turned 30 on Sept. 2.

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