From week to week, Colorado head coach Mike MacIntyre wasn't sure which five linemen would be in his starting lineup last season.
During the nine-game Pac-12 conference schedule, the Buffaloes never used the same lineup two weeks in a row. Injuries and inconsistency were a big reason the line, and therefore the offense as a whole, struggled.
"I think Stanford's offensive line stayed intact all 14 games," MacIntyre said. "We didn't have that luxury. The year before, we had that luxury. So, our offensive line staying healthy will make a big difference for us. Definitely that's what we hope happens."
While injuries took their toll on the line last year, the Buffaloes come into this season with a good deal of experience. Nine linemen have seen playing time and eight of them started at least one game in 2015. Several of them played multiple positions last year.
"The injuries hurt us a little bit, but I feel like it was a good learning experience," senior guard/tackle Shane Callahan said. "We had a lot of guys that came back and learned from that. That was a good experience, to see how you have to shift around (to different positions). I think it'll be an advantage to us this year."
If the Buffs can use their experience to their advantage, this figures to be a better season for the line, and that could be the biggest key to the offense showing improvement.
Before the start of preseason camp in August, BuffZone.com will take a look at each position group for the Buffaloes. In this installment, we take a look at the offensive line.
Position: Offensive line
Returnees: Shane Callahan (Sr., 6-6, 310); Aaron Haigler (Fr., 6-7, 270); Jonathan Huckins (Jr., 6-4, 310); Jeromy Irwin (Jr., 6-5, 300); Josh Kaiser (So., 6-5, 290); Alex Kelley (Sr., 6-2, 315); Gerrad Kough (Jr., 6-4, 290); Sam Kronshage (Jr., 6-6, 280); John Lisella II (So., 6-4, 295); Tim Lynott (Fr., 6-2, 300); Dillon Middlemiss (Fr., 6-5, 290); Isaac Miller (Fr., 6-7, 270); Colin Sutton (Jr., 6-5, 285); Sully Wiefels (Sr., 6-3, 315).
Additions: Sean Larson (So., 6-6, 255; walk-on); Kolter Smith (Fr., 6-3, 280; walk-on); Hunter Vaughn (Fr., 6-7, 275).
Losses: Vincent Arvia (graduated); Ed Caldwell (graduated); Connor Center (left team); Stephane Nembot (graduated).
2015 recap: It was a rough season for the Buffs up front. They gave up 41 sacks, tied for the most in the Pac-12, and had no consistency with their lineup, as nine different players logged at least 119 snaps. Left tackle Jeromy Irwin tore his ACL in Week 2, which eventually led to right tackle Stephane Nembot moving to the left side, where he was less comfortable. Three different players started at each tackle spot, and four players rotated through the guard spots. In fairness, the group did a solid job of run blocking, as the Buffs' five primary tailbacks averaged 4.8 yards per carry and scored a combined 17 touchdowns. Overall, however, it was a mess and it led to the Buffs making a coaching change in the offseason. CU moved offensive line coach Gary Bernardi to coaching tight ends and fullbacks and shifted running backs coach Klayton Adams to the offensive line.
2016 outlook: On the bright side, the Buffs bring back a bunch of experience. Nembot graduated, but he's the only main lineman from last year who isn't back. By all accounts, Irwin's done well in recovery and is expected to regain his starting spot at left tackle. He's up to 300 pounds and stronger than he's ever been. Going into fall camp, none of the other four spots are settled, but the Buffs have good, talented options from which to choose. Lynott, a redshirt freshman, had a great spring and could take the starting job at right guard. Callahan, Huckins and Kough will also compete at guard. Kough spent most of the spring atop the depth chart at left guard. Huckins is also in competition at center, pushing Kelley, who has started 25 consecutive games and was the only lineman to start all 13 games in the same position last year. Kronshage, Haigler and Miller will battle for the job at right tackle. Kaiser, Lisella and Wiefels all got playing time last year and will provide depth. While the Buffs go into fall unsettled on a starting group, the opportunity is there for this to be a better season up front.
Brian Howell: email@example.com, on Twitter: @BrianHowell33.