Posted by ESPN.com's Tim Griffin
1. Running backs: Darrell Scott struggled with injuries all season long in a disappointing freshman season. Rodney Stewart picked up the slack before he sustained a broken leg late in the season. Both looked strong during the spring along with Demetrius Sumler and Brian Lockridge -- a group that helped the Buffaloes produce 270 rushing yards in the spring game.
2. Growth in the secondary: The Buffaloes had to find three new starters this spring. Jimmy Smith showed flashes of being a lockdown cornerback, and safeties Patrick Mahnke and Anthony Perkins look ready to immediately battle for starting positions in fall practice.
3. Offensive line finally healthy: Call this one of the team's most underrated strengths after the strong spring development of tackles Nate Solder and Bryce Givens, guard Ryan Miller and center Mike Iltis. This group could potentially be the North Division's best if it can remain healthy.
1. Who will play quarterback? Cody Hawkins and Tyler Hansen finished the spring in a virtual dead heat. The development of Hansen will be set back after he underwent surgery after breaking his thumb in the spring. And the position is further scrambled after the departure of coordinator Mark Helfrich for Oregon after the spring. Eric Kiesau was hired quickly to replace him, but a new coach is involved with an uncertain mix of players. Not a good sign.
2. Find some receivers: Scotty McKnight's spring injury gave the backups a chance to play. Markques Simas showed some flashes of cracking the rotation, and arriving players like Andre Simmons, Terdema Ussery and Jarrod Darden will have plenty of chances to crack the rotation when fall practice starts. Or, it could be a couple of walk-on receivers jumping into their place.
3. Unsettled defensive front: The Buffaloes will really miss the contributions of players like George Hypolite and Brandon Nicolas in the trenches. Coaches spent most of the spring tinkering with a 3-4 front, but aren't sure if it will fit their current personnel. Colorado will need big contributions from sophomore nose tackle Eugene Goree, senior defensive tackle Taj Kaynor and junior defensive end Marquez Herrod to help fill the gaps.