"The Cowboys suffered two significant ankle injuries Sunday in their loss at New England.
Starting left guard Bill Nagy will miss the rest of the season with a fractured right ankle, owner Jerry Jones said. Also, Jones said that starting running back Felix Jones "might" be out Sunday against St. Louis with a left high ankle sprain.
Felix Jones was injured early in the second quarter on a 7-yard reception from Tony Romo. He limped to the sideline and had his ankle taped by an athletic trainer, but he never returned to the game."