Spring practice kicks off in March, and each Big Ten team will be looking for some key replacements in their depth charts. We're going to take a look at two players on each Big Ten squad who leave big shoes to fill and who might be ready to step in at those spots.
Let's start off with the Michigan Wolverines.
BIG SHOES TO FILL: Mike Martin, DT
Why: Three-year starter anchored the middle of the defensive line. He earned second-team All-Big Ten honors in both 2011 and 2010. Martin appeared in 49 games, starting 37 at nose tackle, and finished his career with 172 tackles, including 25 for loss and seven sacks. His value goes far beyond the numbers, as he consistently took on double-teams and topped the opponent's scouting report before games against the Wolverines.
The skinny: Head coach Brady Hoke, who works directly with the nose tackles, has some work ahead this offseason in trying to replace Martin, the heart and soul of Michigan's defense. Is Campbell finally ready to take the next step? The former blue-chip recruit has the talent but hasn't quite blossomed. Pipkins arrives with a lot of buzz and could work his way into the rotation at a position with few proven players.
BIG SHOES TO FILL: David Molk, C
Why: Four-year starter won the Rimington Trophy in 2011 as the nation's top center. Molk was a consensus first-team All-America selection in 2011. He earned first-team All-Big Ten honors from the league's coaches in each of his final two seasons. He started 41 games at center, and his absence was felt any time he wasn't on the field. Offensive coordinator Al Borges placed a great deal of responsibility on Molk last fall, and Molk delivered for a unit adjusting to a new system.
The skinny: Khory has been the heir apparent to Molk for several years, but his snapping struggles early in the Sugar Bowl sounded a few alarms among Michigan fans. If Khoury isn't the answer, Barnum might be. He started three games at guard in 2011 before being slowed by ankle problems. Miller is an intriguing prospect who needs to bulk up a bit.