How will Stanford replace Aziz Shittu, Brennan Scarlett and Blake Martinez?

Longtime starter Kevin Hogan has graduated, so quarterback naturally represents the highest-profile position battle at Stanford Cardinal this offseason. But there isn't anything new to report there that isn't already common knowledge: Either Ryan Burns are Keller Chryst will win that job. Both are strong-armed, 6-foot-5, 235-pounders who performed well this spring and will be counted to provide a counter-threat to running back Christian McCaffrey.

The Cardinal face a more complicated replacement job on the other side of the ball, where graduation has compromised the interior backbone of their defense. Defensive linemen Aziz Shittu and Brennan Scarlett are both gone, as is inside linebacker Blake Martinez, who plugged gaps right behind them and led the Pac-12 with 141 tackles.

Scarlett led Stanford in sacks, while Shittu set the team pace with 14 tackles for loss. Both proved to be versatile pieces that rescued this defensive line from disaster last year.

The position group entered the season on a tenuous note -- a combination of graduations and early retirements made depth a concern from the very get-go. Then Harrison Phillips tore his ACL just a few series into the year, and the situation reached a critical level. From that point on, Scarlett and Shittu went to work alongside Solomon Thomas to hold down the fort just effectively enough for Stanford's Rose Bowl run.

Thomas is the trio's only returner, and he's expected to be the line's stalwart in 2016. He's skilled enough to rotate between tackle and end, a huge plus considering the fact that the rest of this position group is relatively unproven. Phillips is back from his knee injury, and he showed flashes of dominance in a few early plays against Northwestern last year. Stanford will need to see healthy consistency from him.

To answer the rest of the question marks, the Cardinal are hoping that fifth-year senior Luke Kaumatule -- a 6-foot-7, 295-pound specimen -- can finally deliver steady productivity after a redshirt season dedicated to learning the playbook (Kaumatule has gone through four position changes during his college career). Former tight end Eric Cotton is now on the defensive line, and he's bulked his 6-foot-6 frame up to 265 pounds. Then there's redshirt freshman Dylan Jackson, another tall player who impressed Stanford coaches during his first year on campus. The Cardinal also hope that fifth-year senior Jordan Watkins can turn the corner in his final campaign, as defensive line coach Diron Reynolds knows that depth at this position is of paramount importance against the frenetic offensive pace of the Pac-12.

The void left by Martinez behind the defensive line can't be forgotten, either. Kevin Palma and Jordan Perez, two inside linebackers who saw significant action last year, both return. But Stanford's replacement efforts here go well beyond those two: Noor Davis, Bobby Okereke, and Sean Barton are all in the mix to fill the big shoes left by the Cardinal's tackling machine.