With UCLA star linebacker Myles Jack now out for the year, which injury is the most impactful of the 2015 season so far? SI.com's college football writers make their picks.

By SI.com Staff
September 23, 2015

It’s an unfortunate reality that injuries inevitably derail some team’s seasons. All the preseason projections and hope can quickly get tossed out when the wrong player suffers the wrong injury.

BYU seemed on track to make a run for an undefeated season last year before quarterback Taysom Hill broke his leg and the Cougars lost four straight. Two years ago, Miami began the season 7–0, powered by Duke Johnson, before the running back fractured his ankle against Florida State and the Hurricanes limped to a 9–4 finish.

The 2015 season has already brought a rash of critical injuries, including Wednesday's revelation that UCLA star linebacker Myles Jack would miss the rest of the season with a knee injury. Jack's is one of several injuries that could affect the race for conference titles and College Football Playoff berths. Which injury is the most significant so far? SI.com’s college football writers make their picks:

Gabriel Baumgaertner: UCLA LB Myles Jack and DE Eddie Vanderdoes

Vanderdoes’ absence against UNLV wasn’t readily apparent, but it sure was as BYU’s Adam Hine steamrolled the UCLA defense for 149 yards on 23 carries in the Bruins’ narrow escape over the Cougars. The Bruins had a formidable run-stuffing unit entering the season between Vanderdoes and Kenny Clark. Now, it’s a bigger weakness. Add in the crushing loss of star linebacker Myles Jack (and DB Fabian Moreau for good measure), and the Bruins may need to rely on Josh Rosen and Paul Perkins to win them some shootouts.

Andy Staples: Auburn DE Carl Lawson

An excellent pass rusher can mask a lot of a defense's flaws. With Lawson out, Auburn's defense has been unmasked to reveal...a defense pretty much like the one the Tigers had in 2014.

Pete Thamel: Arkansas RB Jonathan Williams

The Razorback have lost all their momentum from their finishing kick in 2014 and lack any spark on offense after losing to Toledo and Texas Tech.

Brian Hamilton: Williams

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Take your pick at Notre Dame, really, given a schedule that is opening up even more for a playoff run. But I'll go with an injury that occurred before the season even started: the foot surgery for Arkansas running back Williams. Alex Collins essentially picked up where he left off last fall (351 yards, 5.9 yard per carry this season), but the strength of the Razorbacks was in the double-shot of backfield talent in Williams and Collins, who rushed for a combined 2,290 yards in 2014. Instead, a would-be ascendant SEC contender is 1–2. Arkansas's next three games: Texas A&M at a neutral site, then Tennessee and Alabama on the road. This is a program built to be carried through the grisly conference grind by two featured backs. The absence of Williams seems to have threatened the trajectory of the entire operation.

Lindsay Schnell: Notre Dame QB Malik Zaire

The Fighting Irish have suffered a slew of injuries this September, but I think Zaire is the guy they’ll miss most. Yes, backup DeShone Kizer played admirably in wins over Virginia (8 of 12 for 92 yards with two touchdowns, including one game-winning heave) and Georgia Tech (21 of 30 for 242 yards with one touchdown and one interception), but I don’t think this is sustainable. More than pure ability, Zaire was praised for his charisma and personality. The locker room will miss that as the season goes on.

Zac Ellis: Zaire

Yes, the Irish are 3–0 and fresh off a strong 30–22 win over Georgia Tech. But what do we know about Kizer? The redshirt freshman played well against the Yellow Jackets, completing 70 percent of his throws, but that was also his only career start. Prior to filling in against Virginia, Kizer hadn't taken a snap in college. Plus, Zaire had long ago won over teammates as Notre Dame's leader. Can Kizer do the same with games against Clemson, USC and Stanford remaining?

Ben Glicksman: Arizona LB Scooby Wright III

It remains to be seen how long Wright will be out after suffering a torn meniscus in the Wildcats’ 42–32 win over Texas-San Antonio on Sept. 3. In fact, he could return as soon as this Saturday against UCLA. The length of his absence could determine Arizona’s Pac-12 fate, though. Wright racked up 163 tackles, including 29 for loss and 14 sacks, during his All-America sophomore campaign. The linebacker is the heart and soul of the Wildcats’ defense, and the team is unlikely to make a run at the conference crown without him.

AP Photo/Tony Gutierrez

Colin Becht: TCU's many defensive injuries

I'm going to cheat here and take the whole group of injuries that have befallen the Horned Frogs' defense. I had concerns about this defense before the season because it only returned five starters, including zero linebackers. Even for a Gary Patterson-led unit, that seemed daunting to keep up with TCU's sky-high expectations. Now that the Horned Frogs have lost four defensive starters to season-ending injuries, a fifth has yet to play this year, a sixth took a leave of absence and isn't expected back this season and a seventh was arrested Monday night on felony charges, it seems impossible that TCU could maintain an elite defense. Without that, the Frogs will surely fall short of their playoff hopes.

Chris Johnson: Zaire

When Notre Dame lost two of its top three running backs—one to academics (Greg Bryant) and one to injury (Tarean Folston)—Irish fans could take comfort in the offense's ability to move the ball through the air. With Zaire gone for the season because of a fractured ankle, Notre Dame must now rely on a converted defensive back/wide receiver (C.J. Prosise) to shoulder the rushing load and an unproven quarterback. Kizer acquitted himself well in the Irish’s win over Georgia Tech on Saturday, but that was only one game. We’ll see how the redshirt freshman performs during a tough upcoming stretch beginning with an Oct. 3 trip to Clemson.

Ben Estes: Oregon QB Vernon Adams

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Adams’s broken index finger isn’t a severe malady, and there’s a good chance it won’t keep him out of any more games. But this type of injury can end up hampering a quarterback all season. I think this becomes an issue that doesn’t go away, and even if it’s not a significant hindrance for Adams, it could still be the reason Oregon drops one or two more tight games. The finger clearly curbed his effectiveness against Michigan State in a game the Ducks could have won had a few throws gone differently. Oregon won’t win the Pac-12 or make the playoff without its offense operating at peak efficiency, so Adams’s injury will end up being a bigger deal than it seems right now.

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