Jon Kitna knows about filling in for Tony Romo. He did it in 2010, going 4-5 as the starter after Romo broke his left collarbone. He will help do it again this week.
Kitna agreed to terms Tuesday, according to sources, returning to town as the Cowboys' third quarterback.
The Cowboys worked out John Skelton, David Carr, Tyler Thigpen and Richard Bartel, but Kitna was the only quarterback that fit their requirements: A knowledge of the offense and NFL experience.
Kitna retired after the 2011 season and moved back to Washington with his family, with the Cowboys replacing him with Kyle Orton. Kitna played with four teams in 15 seasons, going 50-74 in his career, with a 60.3 completion percentage, 29,745 passing yards, 169 touchdowns and 165 interceptions.
The Cowboys are holding out hope that Romo, who has a herniated disc in his back, can play Sunday. But Romo will not practice this week, and it remains unlikely he will play Sunday. Orton was the only other quarterback on the team's roster after practice squad quarterback Alex Tanney left for the Browns active roster during Thanksgiving week.
The Cowboys will have to make a roster move to get Kitna signed.
-- Charean Williams