Biggest shoes: Colorado

Starters in, starters out. That’s college football. Players’ eligibility expires, and they leave for the rest of their lives, whether that includes the NFL or not.

And they leave behind shoes of various sizes that need to be filled.

Our concern with this series? The biggest shoes -- in some cases Shaq-like size 23s.

Biggest shoes: David Bakhtiari

Quantifying the impact of an offensive lineman is always difficult. Quantifying the impact of an offensive lineman on a one-win team that was either last or near last in the league in almost every offensive category is even tougher. But anyone who followed Colorado the past couple of seasons understands the impact of the 6-foot-4, 295-pounder. He started 11 games at left tackle and yielded 2.5 sacks for the entire season -- meaning he did his part for a team that allowed 50 sacks in 2012. He consistently continued blocks downfield and is a legitimate NFL player.

Stepping in: To be determined…

Though completely reasonable, Colorado was still a bit caught off guard when he decided to jump to the NFL early, so there wasn't much time spent grooming a replacement. At this point – especially with a new coaching staff coming in and shifting to a pistol offense, it’s pretty wide open. We could see someone like Stephane Nembot move over to the left side. Jack Harris is also a possibility -- as is a guard like Jeromy Irwin shifting positions. It’s up in the air – and replacing the two-time second-team all-conference selection won’t be easy.