Sean Weatherspoon out for Falcons-Cowboys game

FLOWERY BRANCH, Ga. -- Linebacker Sean Weatherspoon, one of the leaders of the Atlanta Falcons' defense, will miss Sunday night's game against the Dallas Cowboys with a right ankle injury.

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Weatherspoon, second on the team in tackles and sacks, injured the ankle in Sunday's 30-17 win at Philadelphia.

Coach Mike Smith said after Thursday's practice Weatherspoon and receiver Kevin Cone, who has a groin injury, will miss the game.

The loss of Weatherspoon, a first-round pick in 2010, is a significant blow to the NFL's only undefeated team. He has had 10 or more tackles in four games this season after setting career highs with 127 tackles and four sacks in 2011.

Akeem Dent, a second-year player, will be the primary replacement for Weatherspoon.

Copyright 2012 by The Associated Press