1. Bradley Roby
The Cowboys will be hard-pressed to do better than Roby at this point in the calendar. He was a surprise cut during the Saints' roster crunch and has yet to sign elsewhere.
That said, the 31-year-old is beginning to garner interest. He took a visit with the cornerback-shortened 49ers this week and will likely have a new home before long given his experience in various defensive schemes.
Roby has specialized in man coverage throughout his career. The Cowboys' scheme varies depending on their opponent, but Roby's prowess in man coverage could be a weapon when Dan Quinn dials up the blitz.
Roby didn't produce a great coverage great last season, but he held opposing quarterbacks to a middling 79.4 passer rating when targeted, per PFF. If Dallas wants to get another CB through the door, Roby is their best bet.