BOULDER — With the onset of organized summer workouts just around the corner and the opening of football fall camp less than 12 weeks away, we begin the process of breaking down where the Colorado Buffaloes stand on a position-by-position basis.

First up: Offensive line.

No, it's not the sexiest position on the team (we'll save that for later). But heading into the 2016 season, it's hard to argue there's any more important position on the team if Mike MacIntyre's Buffs are going to take a significant step forward in the win column.

The reasoning is simple.

Given the number of returning starters on defense — impact players who had a big role in last season's improvement — it's reasonable to think the defense will be improved again.

But by almost all measures, CU's offense took a step back last season, and the troubles began up front, where injuries took their toll early and continued to wreak havoc for much of the season. The Buffs ended up using an amazing nine different starting O-line combinations — including three left tackles — with five players making their first career starts, and only one player, center Alex Kelley, starting the same position every game.

Thus, the team that tied for the league lead in sacks allowed in 2014 (23) finished tied for 11th in that category last season (41). Those numbers are even more revealing when you figure Colorado threw 545 passes when giving up those 23 sacks in 2014; last year the 41 sacks came when Colorado attempted 466 passes.

There was also a drop in rushing yards per attempt. In 2014 the Buffs averaged 4.1 yards per rush; last year that number dipped to 3.7.

It's safe to say if the Buffs don't improve on those numbers, it's hard to see the offense turning the arrow back in the right direction — no matter who lines up at quarterback.

And it all begins up front.

What we learned in spring: Heading into the spring, the Buffs still didn't have the services of starting left tackle Jeromy Irwin, who tore his ACL in Week 2 of the season. While not having Irwin available when the Buffs began the process of revamping their offense no doubt hurt, there was a sliver of a bright spot: his absence meant more reps for other players, giving new O-line coach Klayton Adams a good chance to evaluate talent.

Adams spent much of the spring mixing and matching combinations. While it's still quite clearly a work in progress, Adams did get a solid look at a number of youngsters, including resdhirt freshmen Tim Lynott Jr., Isaac Miller and Aaron Haigler. All had their moments, and while Adams no doubt would have liked more time and more practice, he emerged from the spring on an optimistic note.

What's next: While Irwin couldn't participate in spring drills, he did take every advantage of time in the weight room and he's expected to be cleared for full go for summer drills. He's now tipping the scales well past 300 pounds and it's a solid 300 pounds. In Mike MacIntyre's words, he looks like an NFL tackle, and if he picks up where he started in 2015, he'll have a chance to prove that point.

What will be extremely important for all of the linemen in the summer will be continued conditioning and weight training as well as classroom work. One thing evident from spring drills is that co-offensive coordinators Brian Lindgren and Darrin Chiaverini want to step up the pace of play. That means the linemen not only have to know the offense, but they need to be in tip-top shape — especially if they plan on using the altitude to their advantage at home.

Fall camp storylines: If Irwin's recovery continues to be on pace, he could be a terrific left tackle, and he'll be a team leader in every sense of the word. At right tackle, the Buffs will need to find a replacement for three-year starter Stephane Nembot, but the candidates are solid: Sam Kronshage started six games at tackle last year and Haigler had an impressive spring.

Also emerging from an impressive spring with a place atop the depth chart is Lynott at right guard, but there are two very interesting battles brewing at the two remaining spots.

At left guard, a pair of 10-game starters from last year — Gerrad Kough and Jonathan Huckins — are tied atop the depth chart, putting Huckins in what is surely a rare if not unique spot for an O-linemen: tied atop the depth chart at two positions.

Yes, Huckins is also listed as co-number one at center, where Kelley has been the starter every game for the Buffs for the last two years.

It will mean some heated battles when fall camp rolls around, and that's a good sign on two fronts. One, competition between players who have starting experience is a great sign because it makes everyone involved better. Two, it means there will be depth, something that hasn't been overly abundant.

Note: CU's “pencil” depth chart is the one that has been released to various magazines around the nation for their summer preview specials. It includes players who were injured and did not participate in spring but are expected to be ready for summer conditioning. It does not include players who have yet to practice with the team, such as incoming freshmen and transfers.

Pencil depth chart:

Left tackle: Jeromy Irwin, Isaac Miller, John Lisella II.

Left guard: Gerrad Kough OR Jonathan Huckins, Josh Kaiser, Colin Sutton.

Center: Alex Kelley OR Jonathan Huckins, Sully Wiefels.

Right guard: Tim Lynott Jr., Shane Callahan.

Right tackle: Sam Kronshage OR Aaron Haigler, Dillon Middlemiss.

Incoming players who could figure into the mix: The Buffs signed four offensive linemen, but it's extremely rare for a true freshman offensive lineman to make an immediate impact.

Contact: Neill.Woelk@Colorado.edu