What's hot from Senior Bowl practices

MOBILE, Ala. -- Both the North and South teams held practices Wednesday in preparation for the Senior Bowl. Here is what's hot:

Run of injuries: In addition to Oklahoma cornerback Aaron Colvin, who tore his ACL, three players were out of Wednesday's practice with injuries: Alabama defensive end Ed Stinson, Fresno State tight end Marcel Jensen and Tennessee offensive tackle Ju'wuan James. During the morning practice, North team defensive end James Gayle (Virginia Tech) left with an arm injury. Gayle is the No. 81 ranked prospect in May's draft according to Scouts, Inc.

Martin tried at guard: Notre Dame left tackle Zack Martin, considered one of the top players in Mobile this week, saw extensive action at left guard during Wednesday's practice. He was impressive. Martin stands at 6-foot-4, 308 pounds and could be better suited as an interior lineman. At one point, Martin lined up at left guard with Clemson's Brandon Thomas at left tackle. Both players have shown well this week and could be among the top offensive linemen in the draft.

Donald impresses: Pittsburgh defensive tackle Aaron Donald has drawn buzz this week and had another strong performance Wednesday. The 'wow' factor on Donald is obvious: He's been in the backfield more than any other defensive lineman. Donald (No. 32) isn't ranked as highly as Minnesota's Ra'shede Hageman (No. 22) on our Scouts, Inc. ranking, but Donald has stood out more than Hageman this week.