At this point, we don't know if Mathieu is a great CB or not. We know he's an AMAZING nickel back, but being a true cornerback is a different skill set. Honestly, as often as we play our nickel package, I am not really concerned with whether Mathieu makes the transition to being a full-fledged CB or not. I'm not as high on Claiborne as a lot of other people seem to be. I think he's good, but I haven't seen anything great. Right now, I wouldn't put him as anything higher than a 4th round draft pick. We'll see if he's ready for a break-out season. Basically the only time we saw Simon play was against Julio Jones, which was quite impressive. He made some mistakes, but that's expected. We're all excited to see more out of him, but if Mathieu takes over as a full-time starter it will be another year until Simon starts.
But, that's the thing; he's tall and has shown great athleticism. He's made plays on quick passes as well as on long ones. I'll agree that he lacks the PT to be fully characterized at this point, but he's absolutely made the most out of his limited reps. He also had a pick in the Cotton Bowl, and looked very impressive in the spring game.