MOBILE, Ala. — News, notes and observations from day three at the Senior Bowl:

1. South Florida safety Nate Allen has been impressive this week. Not only does he display good instincts and ball skills in coverage, he also possesses by far the best footwork of any safety on the South. Allen looks fluid when asked to get out of his breaks and does a nice job getting up to speed quickly. He’s very quietly been one of the most impressive prospects here.

2. Meanwhile, USC’s Taylor Mays continued to struggle generating any kind of burst when asked to click and close and routinely getting high in his drop and being forced to gather himself in coverage. On top of that, he lacks the type of instincts needed to consistently get good jumps on the ball and always looks to be playing from behind. If I had my choice between Mays and Allen at this stage, my pick would be Allen.

3. I haven’t been the biggest fan of LSU’s Ciron Black this season, but I did come away impressed with his performance Wednesday when he lined up some at guard. He exhibited good power at the point of attack, looked smooth through contact and did a nice job staying on blocks. I never considered Black to be a legitimate left tackle prospect, but the brief preview we got of him at guard was promising.

4. Another guy who flashed at another position Wednesday was Troy defensive end Cameron Sheffield, who got some time at linebacker during one-on-one coverage drills and surprisingly showed well. He was fluid when asked to change directions, maintained his balanced and generated a good closing burst toward the football. Plus, the fact that he possesses the first step needed to rush the passer makes me think Sheffield could end up being a contributing 3-4 OLB.

5. Unfortunately for South Florida’s George Selvie, he wasn’t nearly as impressive as Sheffield in coverage. Selvie looked stiff and was absolutely out of his element in space. He also hasn’t faired real well generating pressure off the edge all week and looks little more than a reserve-type lineman at the next level.

6. Another guy who has failed to impress is Texas DT Lamarr Houston, who lacks ideal size and isn’t overly explosive off the ball. He’s really struggled generating much push on his bull-rush and doesn’t use his hands well enough to disengage from blocks and get after the ball. Houston routinely struggled to get off the snap count on time Wednesday and looks like a guy who was simply able to beat up on bad competition in the Big 12.

7. Tulane wideout Jeremy Williams isn’t the most explosive of vertical threats, but the guy is a powerful route runner who showcases a enough speed to track the football and adjust to the throw. Williams caught everything throw his way yesterday, and his combination of physicality, savvy and athleticism allows him to consistently beat press coverage and separate out of his breaks. He’s another guy who has quietly had a solid week.

8. It’s obvious when watching Tennessee defensive tackle Dan Williams that the man is one powerful individual. He’s consistently able to overwhelm opposing linemen on contact and generates a great deal of power from his lower half. However, he hasn’t quite had the type of week many expected. He’s not a guy who is overly explosive off the snap and doesn’t do a good job using his hands to disengage from blocks inside. I’m not saying that there isn’t a place for him in the NFL, but I don’t think he’s worthy of being graded out as an impact-caliber defensive lineman.

9. He may be out of his element in coverage, but South Carolina outside linebacker Eric Norwood knows how to rush the passer. He was absolutely dominant Wednesday, beating running backs/fullbacks with ease in one-on-one drills, and I definitely seem him as a guy who can create pressure off the edge as a 3-4 rush linebacker.

10. Finally, Alabama offensive guard Mike Johnson isn’t the most physically imposing of lineman out there, but at 6-5 he plays with good leverage and can really stick to blocks through the play. He did a nice job maximizing his reach into blocks and can generate good power on his punch on contact. He grades out as a potential dirty starter at the next level.

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