Down
enlarge shrink
2015 College football season: The great unknown
1:13 | College Football
2015 College football season: The great unknown
Thursday September 3rd, 2015

With the college football season set to kick off Thursday night, we're in the last few hours of the old optimist's adage of the preseason: For now, every team is undefeated. But a less frequently used phrase is equally true: As of now, every team is winless.

Just as the former statement of hope cannot remain true, neither can the latter. However, pessimism does reign supreme in one regard. All but one team will not win a national title this year. Here's why every team in the AP poll's top 25 won’t be that lone exception.

College Football
2015 preseason Crystal Ball: SI picks the playoff, Heisman, hot seat, more

No. 25 Tennessee

The Volunteers have risen back into contention for conference and national titles with a talented group of starters capable of competing with any team in the country. But as the season wears on, injuries will take their toll and reveal a lack of experienced depth. Tennessee has already lost four contributors before the season has even started. It won't make it through 12 games.

No. 24 Missouri

Have you looked at the Tigers' defensive line? The unit that was the strength of both their SEC East championship teams is finally showing signs of depletion after the departures of Michael Sam, Kony Ealy, Shane Ray and Markus Golden—and that was before Harold Brantley was lost for the year due to injuries from a car crash. An inexperienced group of receivers—no returning wideout caught more than five passes in 2014—won't help the offense, either.

No. 23 Boise State

Maybe the Broncos are talented enough to crash to the playoff, but their schedule will never allow it. Even if Boise State goes undefeated, its best wins would likely be over BYU, Utah State and Washington. The Broncos are probably headed to a postseason game in Glendale, Ariz., but it'll be the Fiesta Bowl again, not the national title.

No. 22 Arizona

Even with Scooby Wright emerging as the top defensive player in the country, the Wildcats still ranked 63rd in yards allowed per play. And while a Rich Rodriguez offense could be relied upon to make up for that, Arizona loses three starters on its offensive line, and one of its expected replacements, center Carter Wood, is out for the season with an injury.

No. 21 Stanford

The Cardinal's ascent in national reputation has been built on stout defensive play, so why would they reach new heights in a year when they return just three defensive starters? With a completely rebuilt defensive line and secondary facing some highly talented offenses in the Pac-12, Stanford won't escape unscathed.

No. 20 Wisconsin

Despite a strong running game and one of the better defenses in the Big Ten, the Badgers don't have the overall talent to win two possible games on their schedule: their season opener against Alabama and a potential Big Ten championship game matchup with Ohio State or Michigan State. Joel Stave has given little reason to believe he's anything close to a championship-caliber quarterback.

College Football
Which surprise teams can get off to hot starts this season? #DearAndy

No. 19 Oklahoma

There are bound to be some bumps in the road with a new offensive system—Lincoln Riley's Air Raid offense—and a new starting quarterback—junior transfer Baker Mayfield. Even if both of those transitions go smoothly, the Sooners must also contend with the loss of 145 career starts on their offensive line.

No. 18 Arkansas

As powerful as the Razorbacks' running game was last year, their breakthrough came because of a defense that became one of the best in the country. The losses of Trey Flowers, Darius Philon and Martrell Spaight leave Arkansas without the proven playmakers in its front seven to match its offense's physicality on defense. And then there's the brutal schedule that includes trips to Alabama, Ole Miss and LSU.

No. 17 Ole Miss

The Rebels have a loaded defense and some pass-catching weapons in Laquon Treadwell and Evan Engram. Sadly Treadwell and Engram might never be used to their full potential due to Ole Miss's shaky QB situation. And unlike some other SEC teams with uncertainty under center, Hugh Freeze's squad doesn't have the Heisman-caliber running back to make up for it.

No. 16 Georgia Tech

Even if the Yellow Jackets' triple-option offense overcomes the loss of all of its running backs, there's still the problem of a defense that is simply too porous. Georgia Tech ranked 111th in the country in yards allowed per play (6.2) and 118th in third-down defense (46.75% third-down-conversion percentage allowed).

No. 15 Arizona State

The Sun Devils might prove to be a playoff team through three quarters, but will they be able to sustain that through the end of their games? Although Arizona State's defense is experienced, it was one of the worst in the final stanza last year, allowing 8.6 points per fourth quarter (101st in the country). That's bound to bite Todd Graham's squad at some point this season.

College Football
Preseason Heisman Watch: Sizing up favorites, second tier, long shots

No. 14 LSU

LSU could be a playoff favorite—if only it had an answer at quarterback. After a full season and off-season, we're still waiting for that quarterback solution to emerge. And in a rarity in Baton Rouge, there's reason for concern on the defensive line, which loses two starters on the end and has almost no depth at tackle after the departures of Trey Lealaimatafao, Travonte Valentine and Maquedius Bain.

No. 13 UCLA

Maybe Josh Rosen will prove to be the Bruins' next star quarterback, but a true freshman, even as highly touted as he is, is likely to show some growing pains. Those will be difficult to mask in the Pac-12 South against a schedule that features road games at Arizona, Stanford and USC.

No. 12 Clemson

Good luck keeping star quarterback Deshaun Watson healthy with an offensive line that returns just one starter. If Watson goes down again, 2014 didn't offer positive signs for the Tigers' ability to move the ball without him. Clemson averaged just 20.7 points per game in regular season games that he missed all or most of. That'd be a lot of pressure to put on a talented but young defense breaking in eight new starters.

No. 11 Notre Dame

College Football
Ronnie Stanley returns to Notre Dame better than ever; Week 1 Walkthrough

Injuries ravaged the Fighting Irish's defense last year and were a major contributor to their freefall in the second half of last season, but are we at all concerned about Notre Dame's depth given how well the backups fared last year? Defensive tackle Jarron Jones is already injured, and more players will certainly pick up knocks. The schedule doesn't leave much margin for error. Especially noteworthy, the Irish must host USC a week after playing Navy. The only teams Notre Dame has beaten the week after playing Navy in the past eight years are Wake Forest in 2011 and Purdue in ’12.

No. 10 Florida State

The Seminoles have no shortage of talent, but their lack of experience is likely to produce some inconsistency. Not to mention their new starting quarterback (Everett Golson) who has a knack for inconsistency due to his proneness to turnovers. An entirely rebuilt offensive line isn't likely to help Golson.

No. 9 Georgia

Take your pick: There's the quarterback situation, the rough schedule, or maybe you just don't have faith in Mark Richt's ability to win a championship. New starter Greyson Lambert's career 11-to-13 touchdown-to-interception ratio doesn't inspire much confidence, and the Bulldogs drew the worst possible SEC West crossover matchups with games against Alabama and Auburn.

No. 8 USC

The losses of Buck Allen and Leonard Williams leave the Trojans with some big holes to fill at major roles and no clear solutions. Can Justin Davis or Tre Madden step up to replace Allen? Can they at least stay healthy? And facing a conference slate that's loaded with elite quarterbacks, who's going to replace Williams' disruption to the passing game? Linebacker J.R. Tavai's (13.5 tackles for loss, seven sacks) departure hurts here, too.

No. 7 Oregon

Is Vernon Adams really ready to lead a team to a national championship after not even getting on campus in time for the start of fall camp? He'll have to be at full speed by Week 2 for the Ducks to get by Michigan State. A key part of Oregon's return to the championship game last year was a defense that was a suitable match for its always talented offense. The loss of defensive end Arik Armstead and cornerback Ifo Ekpre-Olomu (one of three departing starters in the secondary) puts the continuation of that defensive prowess in jeopardy.

No. 6 Auburn

Will Muschamp may be a defensive guru, but we're expecting an awful lot from him to turn the Tigers into a championship-level defense one year after they gave up 5.7 yards per play. Fixing a secondary that allowed 7.3 yards per pass attempt in 2014 might take more than an off-season.

No. 5 Michigan State

The Spartans will feel Pat Narduzzi’s absence when a secondary that must replace Trae Waynes and Kurtis Drummond struggles to live up to the high expectations of a Michigan State defensive backfield. Quarterback Connor Cook is steady but has never been considered the type of transcendent talent that can single-handedly lead an offense. That’s what’s being asked of him in an attack that lacks a proven rushing threat and whose top returning receiver had just 400 yards last year. And then, of course, there’s the Ohio State roadblock to deal with.

No. 4 Baylor

Schedules are set years in advance, so you have to cut the Bears some slack, but they failed to address the primary obstacle to their playoff path last season. A nonconference slate of SMU, Lamar and Rice means Baylor won’t have a chance to pick up a marquee victory until its Nov. 14 date with Oklahoma. All it will take to put the Bears’ playoff hopes on thin ice is one slipup. The loss of their actual quarterback (Bryce Petty) and defensive quarterback (linebacker Bryce Hager) is likely to produce at least one.

No. 3 Alabama

College Football
Week 1 college football picks: Utah vs. Michigan, Texas vs. Notre Dame, more

The Crimson Tide boast a ton of talent on defense and in their backfield, but can they really expect to win an SEC and national title with a one-dimensional offense? Nick Saban and Lane Kiffin pulled a rabbit out of their hats with Blake Sims last year, but this year’s QB competition, with its constantly changing leader, seems less likely to end so pleasantly. A few SEC defenses are bound to stymie Derrick Henry if he doesn’t get some help.

No. 2 TCU

The offense can’t get much better, and the defense is likely to get worse after losing six starters, including five in its linebackers and secondary. The Horned Frogs got a little lucky to go 3–1 in games decided by four points or less, and even though they get Baylor at home, road trips to Minnesota, Oklahoma and Oklahoma State make this year’s schedule more difficult. After last season huge leap forward, expect some regression to the mean.

No. 1 Ohio State

It’s hard to find an argument to knock the Buckeyes on paper, but there’s a reason repeat champions are rare. Even a master motivator like Urban Meyer can struggle with complacency on a team coming off of a national title. Meyer’s 2009 Florida team suffered from it, so don’t be surprised to see it happen again to Ohio State. Or, I don’t know, maybe Kansas wins it all.

SI Apps
We've Got Apps Too
Get expert analysis, unrivaled access, and the award-winning storytelling only SI can provide - from Peter King, Tom Verducci, Lee Jenkins, Seth Davis, and more - delivered straight to you, along with up-to-the-minute news and live scores.