The Atlanta Falcons will be forced to go the rest of the way without cornerback Brent Grimes.
In a surprising development, Grimes is done for the season after suffering an Achilles injury on Sunday, coach Mike Smithannounced Monday.
Grimes exited the Falcons' 40-24 win over the Kansas City Chiefs with what was believed to be a calf injury. Smith said after the game he was unsure how much time Grimes would miss.
Grimes -- who received Atlanta's franchise tag in the offseason -- moved to right cornerback after the Falcons acquired Asante Samuel in a trade with the Philadelphia Eagles. Pairing the two veterans put Atlanta in position to greatly improve its pass defense in 2012. Now the team must regroup on the fly.
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