I've been saying it for weeks. Cox should have been playing since Week 1. He's definitely better than Jaylon was, and Cox can not only cover well in coverage, he's got the size, strength and speed to either run you down trying to run around the edge on him or trying to run at him.
I said it before, what in Hades was Dan Quinn waiting for all of these weeks, especially after recently finding out that the Cowboys had been trying since this past offseason started to find a trading partner for Jaylon Smith. If you knew you didn't want Jaylon Smith anymore before the season started, why did you continue to start him while keeping Jabril Cox either inactive or standing on the sidelines all of these weeks???
Talk about a royal screw up. I wonder who was responsible for this delay?