We'll get this out of the way up front: this fall, Boise State is going to field its worst team since 2007. We can haggle about the number of starters the Broncos truly return, we can debate on the likely quality of the new young stars, and we can negotiate whether experience matters when BSU is projected to play just one Top 30 team and three Top 60 teams. But I am confident in saying that, after four years that saw them rank eighth, seventh, first and fourth in the F/+ rankings, the Broncos will not field a Top 10 team this fall.

Beyond that, everything is gray. Top 15? Top 25? Top 50? No idea whatsoever. (Okay, some idea -- they're not going to be out of the Top 50.) Chris Petersen and company must replace the winningest quarterback of all-time (Kellen Moore), a first-round running back (Doug Martin), their No. 1 wideout and No. 1 tight end (Tyler Shoemaker and Kyle Efaw), two all-conference linemen (tackle Nate Potter and center Thomas Byrd), five of their top six defensive linemen (including first-rounder Shea McClellin, third-rounder Tyrone Crawford and sixth-rounder Billy Winn), their leading tackler (Byron Hout) and their top four tacklers in the secondary. And while it is safe to say that Boise State's status as an elite program will not change over the long haul … there have to be some growing pains, right?

Most publications and preseason polls seem to be following the same trend and sticking Boise in the No. 20-25 range. This makes a good amount of sense. I see Boise State basically going through what TCU experienced last year: the team will be mediocre in September, good in October and great in November. Unfortunately, the Broncos play four of their five best opponents before October 7. They are almost certainly going to lose more than one game for the first time since 2007, but they still might not lose more than two.

Related: Check out Boise State's statistical profile.

Last Year

Here's what I said about Boise State last summer:

[H]ow is it possible that a team like 1959 Ole Miss could be one of the best ever when they didn't have a perfect record? The answer, of course, is that when we use numbers we tend to weight the entire season equally. At least, I do. And honestly, in the end, individual wins and losses don't mean that much. That Ole Miss team reached No. 1 because they were, quite simply, incredible. They gave up three touchdowns all year -- two on drives of less than 10 yards and one on perhaps the greatest punt return of all-time. They averaged well over 30 points per game in an era where that didn't really happen. They were an unbelievable team. But they lost a game. Granted, it was to the No. 28 team of all-time. Granted, it was on the road. Granted, it took two goalline stands and the aforementioned greatest punt return ever to take them down. And granted, almost every team below Ole Miss on that list would have lost to that team on that night, too. But it doesn't matter. They lost, therefore they weren't great enough. […] Boise State had a Heisman finalist at quarterback, incredible skill position depth, and perhaps the best set of lines, offensive and defensive, in the country. They were as big and fast as a great major conference team. They manhandled Virginia Tech in the trenches, and they had no serious trouble with Oregon State (they took them out by almost the same margin that Oregon did, only the version of Oregon State they played had James Rodgers). They didn't get a chance to play any other major conference teams, of course, because for the fourth consecutive year they were stuck playing a fellow mid-major in their bowl. But they proved everything they possibly could with the schedule they had. But they lost a game. And to a WAC team, no less. Granted, it was to No. 28 Nevada. (Symmetry!) Granted, it was on the road. And granted, it took two extremely makeable field goals missing the mark to take them down. But they lost. And if they lost to Nevada, how could they possibly have competed with great BCS teams, right? We can just write them off as beneficiaries of a cake schedule and call it a night, right? I don't know if Boise State could have beaten Auburn in the national title game, but I guarantee they would have hung around. Instead, it was just another missed opportunity for the underdog Broncos to prove that they are no longer underdogs, even against the big boys. […] This is still basically a two-game schedule. Trips to Fresno State and San Diego State could be interesting, but for the most part Boise State's season will be defined by their Georgia Dome battle against Georgia on Labor Day Weekend and their November 12 battle with TCU in Boise.

Indeed, Boise State's 2011 season was completely and totally defined by those two games. The Broncos pantsed Georgia in Atlanta to start the season, executing the most technically sound offense in the country and unleashing a ferocious pass rush on Aaron Murray. But as always, they began to fade in pollsters' eyes as they played no-name teams (despite a couple of those no-names -- Toledo, Tulsa -- being quite strong), and when a thoroughly depleted BSU secondary was torched by TCU in an upset loss, the nation took the opportunity to forget all about BSU.

It is impossible to overstate just how good Boise State was over the first half of 2011. The team that finished first in the 2010 F/+ rankings (yes, ahead of Auburn) likely would have graded out right alongside Alabama and LSU had they not trailed off in late-October. Alas, Kellen Moore's storied career ended with a thorough beating of Arizona State in the Maaco Las Vegas Bowl instead of on the BCS stage. And then, every familiar name departed, making way for a batch of soon-to-be familiar names.

Offense

Since 2008, eight teams have had to replace quarterbacks who had finished in the top five of the Heisman voting: 2008 Hawai'i, 2008 Oregon, 2009 Missouri, 2009 Oklahoma (we'll say they lost Sam Bradford in 2009, since he barely played before getting hurt), 2009 Texas Tech, 2010 Florida, 2010 Texas and 2011 Auburn. On average, those teams averaged an Off. F/+ ranking of 12th in their big-time quarterback's final season … and 59th the next season.

Florida fell from 10th to 66th without Tim Tebow, Hawaii fell from 19th to 80th without Colt Brennan, Auburn fell from first to 55th without Cam Newton, and due in part to his unexpected injury, Oklahoma fell from first to 99th when Bradford went on the disabled list. Only Oregon (17th to 15th) and Texas Tech (eighth to 11th) avoided serious regression. As a whole, despite quality recruiting across the boards (Hawai'i aside), most of these teams still inevitably slipped when their legend left.

Next up in the "replacing a legend" competition: Boise State. It appears that longtime backup Joe Southwick is the leader following a solid spring game, but he will have to continue to work to fend off mobile sophomore Grant Hedrick, redshirt freshman Jimmy Laughrea and freshman Nick Patti, who was in for spring. Southwick certainly showed decent proficiency in his given opportunities; he completed 77 percent of his garbage time passes last year, though as is typical in garbage time, most of them didn't really go anywhere. Boise State isn't known for reeling in the blue-chippers, but Southwick was a mid-three-star signee (according to Rivals.com), and the other three were all high-threes.

Whoever wins the job will have the luxury of handing off to D.J. Harper. A sixth-year back who has suffered multiple knee injuries in his five years, Harper was encased in glass for much of the spring; he has averaged 5.1 yards per carry for his career, and he did manage a plus-10.2 Adj. POE last season (meaning he was about a touchdown and a half better than the average running back given his carries, blocking, and opposition). He and Drew Wright will likely perform reasonably well in replacing Doug Martin in the backfield, especially if the line comes together.

As I always say about injuries, they are devastating in the present tense and beneficial in the future tense. Boise State faces the prospect of losing two all-conference linemen (center Thomas Byrd and tackle Nate Potter) who combined for 77 career starts in their careers, but Byrd spent much of 2011 injured, and likely new starter Matt Paradis, who began the season as a third-stringer, actually got a reasonable amount of experience. In all, nine Broncos started at least one game last year, and five return, albeit with just 41 career starts.

In losing wideout Tyler Shoemaker, tight end Kyle Efaw and running back Doug Martin, Boise State must replace a trio of pass catchers who snagged 72 percent of the passes thrown their way and averaged 9.0 yards per target. That seems intimidating until you realize that the new No. 1s at these positions -- Matt Miller, Gabe Linehan and Harper, respectively -- combined for an 80 percent catch rate and averaged 8.2 yards per target.

One can never assume a smooth transition when No. 2s become No. 1s, but let's just say that the receiving corps, which also returns Mitch Burroughs, Dallas Burroughs and the oft-tantalizing Geraldo Boldewijn, is the least of Boise State's concerns. Their success will be determined mostly by whether the new starting quarterback can pull off a reasonable impersonation of Kellen Moore's incredible stat line (74 percent completion rate, 1.6 percent sack rate, 8.4 yards per pass attempt).

And with all the turnaround, it is easy to almost miss the fact that Boise State has a new offensive coordinator this year as well. Robert Prince, last year's receivers coach and passing game coordinator, takes over in that seat.

Defense

Honestly, I can talk myself into the Boise State offense. There is a wealth of options behind center, D.J. Harper is still kicking around, and I've seen just enough of Matt Miller and the Burroughs brothers to assume that -- with the same quality offensive coaching and play-calling to which we've grown accustomed (assuming that doesn't change with Prince in charge) -- the Broncos will still field, at worst, a Top 20 or 30 offense.

But here's the deal: while offense has earned Boise State plenty of attention, the defense -- particularly an incredible defensive line -- has been the difference-maker, the thing that has moved Boise State from fun novelty to a national power. The Broncos have ranked in the nation's top ten in Def. F/+ in each of the past four seasons; they even did so last year despite an incredible number of injuries in the secondary. The reason? An absolutely incredible defensive line. That said line lost five of its six best players scares the bejeezus out of me.

Of course, even a world-class defensive line could not prevent Boise State from springing some leaks last fall. Pile up enough injuries, and eventually any defense will break down. By the end of 2011, 16 different Boise State defensive backs had logged at least five tackles. Of those 16, only eight played in all 13 games; most of the lost time came at the cornerback position. Starting exploding drummer cornerback Jerrell Gavins was lost after three incredible games (he had already picked off three passes and broken up three more). Corners Ebenezer Makinde and Bryan Douglas played in just seven. Lee Hightower? Eight. Jamar Taylor? Nine. Eventually, and predictably, the defense wilted.

Boise State defense (First 3 games): 24.4 Adj. PPG

Boise State defense (First 4 games): 17.9 Adj. PPG

Boise State defense (Next 3 games): 29.5 Adj. PPG

Boise State defense (Last 3 games): 21.8 Adj. PPG

A defense that had allowed just 361 yards per game to Georgia and Toledo (each Top 25 offenses according to F/+) allowed 364 per game to Air Force and UNLV; then, Casey Pachall and TCU came to town. Pachall completed 24 of 37 passes for 473 yards and five touchdowns, and Boise State lost on the blue field for the first time since, I believe, 1849. (Okay, 2005.) The defense rebounded, but the damage was done.

So now the Broncos head into 2012 with the exact opposite depth distribution as they saw last season. Tackles Ricky Tjong-A-Tjoe and Mike Atkinson are the only returning linemen who made more than 9.5 tackles last year, but the secondary has loads of experience. Junior college end Demarcus Lawrence had a lovely spring, and sophomore end Tyler Horn made plays in limited experience (2.5 of his 5.0 tackles were for loss), but this team will be relying on the "5" portion of its 4-2-5 to do a good majority of the damage to opposing offenses. Gavins returns, as does senior corner Jamar Taylor, who proclaims to have allowed just two touchdown passes in two years. They should be spectacular, and safeties like Jonathan Brown and Dextrell Simmons should be able to step into the starting lineup and thrive.

I have little fear about the two-man linebacking corps either. Byron Hout and Aaron Tevis are both gone, but both J.C. Percy and Tommy Smith showed similar proficiency in their opportunities last year. The question for me is entirely based around the line. Ends Shea McClellin, Tyrone Crawford and Jarrell Root combined for 30 tackles for loss and 15.5 sacks, and tackle Billy Winn threw in eight and three respectively. Unlike TCU's 4-2-5, which succeeds primarily by leveraging plays toward its really fast linebackers and safeties, Boise State has thrived by imploding an offense from within. That will not be the case in 2012.

Defining Success

Boise State fans should adopt the 2011 TCU model as their benchmark this season: ignore September results and hope that your squad catches fire later on. Trips to both Michigan State (on August 31) and Southern Miss (October 6) could mean trouble for the Broncos, but they should expect to plow through most of the Mountain West slate, and if they were to finish with double-digit wins again, that would have to be considered a rousing success all things considered.

Prognosis

Because of 2011 injuries, the Broncos can make a couple of interesting claims when it comes to returning starters. They lose six offensive starters … but return seven; guard Jake Broyles started the first three games before injury, and fullback Dan Paul started 2010 but missed 2011. They lose nine defensive starters … but return three, including Jerrell Gavins. (Or, depending on who's massaging the math, maybe they return more than that.)

Again, this will be the worst Boise State squad in quite some time. And they should still expect to only fall to about 9-3 at worst.

This team is too deep, too proven, and too well-coached (and, for that matter, too good on special teams) to drop below that. Youngsters like freshman Nick Patti, sophomore Matt Miller, sophomore Demarcus Lawrence, etc., should have this team right back among the elite soon enough, even if they take a lick or two in East Lansing to start this coming season. (Then again … Michigan State has a lot to replace too, so …)

For more on Broncos football, visit Boise State blog OBNUG, plus SB Nation Denver.

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