Notebook: Defense building depth 

February, 8, 2013
2/08/13
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As long as Greg Mattison is Michigan's defensive coordinator, he will expect perfection. He demands a lot out of his players because he knows what it takes to reach the NFL.

The 2013 class for Michigan is all about getting to the next level and bringing in players who can help Michigan get there.

Defensive line

No. 1 CB Marshall: "Nobody Remembers Second"
Five-star cornerback Iman Marshall, No. 4 overall in the ESPN 300, explains how he turns into a "monster" on the field and what motivated him to climb the ESPN player rankings.
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