Will USC's front seven be enough this season?

It might never rain in Southern California, but USC coach Clay Helton is certainly feeling a deluge in Los Angeles. Cornerback Isaiah Langley's arrest and suspension just added to the once-shrinking list of problems at USC, the most pressing of which (on the field) is a ravaged front seven.

A stout unit in 2015 will have to move on without impact players such as Su'a Cravens, as the Trojans will return just one starter to their 5-2 front this season. Not usually a recipe for success.

Don't get me wrong, USC has plenty of skill up front. Helton will have a group that combines to have almost enough recruiting stars to rival the Milky Way's.

With everyone back on offense (save for quarterback Cody Kessler), Helton just needs this group to develop and mesh (and a QB to emerge) to make this team a real Pac-12 contender. But will the talent up front be able to coalesce in time? That's something Helton's is concerned about heading into this season.

"The defensive line has not gone through a lot of wars," Helton said Thursday, per the Los Angeles Daily News. "There is uncertainty at linebacker."

Sure, the defensive line (and the front seven) be untested, but they won't be completely green -- something that seems to have gone unnoticed. All but one projected starter played in at least 12 games for the Trojans last season, save for Malik Dorton (2 G).

With that in mind, there's some reason to be optimistic about this underratedly experienced unit heading into this season.

Linebackers Have High Ceiling

As Andy Green over at Conquest Chronicles writes, outside linebackers (who essentially act as defensive ends) in USC's 5-2 system are "are rarely asked to drop into coverage." USC's elite secondary will be tasked with covering receivers, leaving the two OLB's with a much less complex assignment: rush the passer and stop the run.

For an untested player whose head will be spinning anyway, taking coverage off their plate will instill them with confidence and piece of mind. That fact will make life a lot easier for Uchenna Nwuoso and Porter Gustin, who figure to fill those outside 'backer spots.

A true freshman last season, Gustin has already started to make a name for himself in Los Angeles. The former four-star recruit was a formidable pass rusher last season, earning two starts (14 GP) while dropping 5.5 quarterbacks to the mat. Count Gustin off Helton's list of worries -- he has the potential to break out and become one of the premier pass rushers in the conference.

Starting his third year on the field for the Trojans, don't mark down Nwuoso as completely green either. He's gotten reps in every game in the last two years, and when he was on the field, he was a tackling machine. The former three-star recruit's 31 tackles last season made him second amongst returning front seven players, behind just phenom Cameron Smith. He's smaller and speedier than Gustin, making him better served to defend the run. In that respect, the pair of outside linebackers seems to complement each other well.

Up the middle, lone starting returnee and freshman All-American Smith should be a calming presence at middle linebacker. He's the real deal -- a high motor run stopper that is well respected among his peers, earning USC's Johny McKay Award for "competitive spirit."

Smith will be flanked by former blue-chipper and weak inside linebacker Osa Masina, could be another formidable force after playing twelve games as a true freshman. He's a smart, quick player that could wind up being a big boon against the run for the Trojans.

Fellow 'backers Michael Hutchings and Quinton Powell should also provide valuable competition and insurance should any of these players falter.  They could start at most programs across the country, and have a fair shot at nabbing significant playing time. Depth shouldn't be an issue.

Led by Smith, this linebacking corps earned a lot of valuable game experience last season. Any sort of jitters that remain amongst this gifted unit should be assuaged by a simpler system that gives players clearly defined roles. With all of these pieces in place, there's no reason to expect USC's youth at linebacker to be a liability, or anything close to one. Don't expect much of a dropoff -- this unit could become one of the best in the Pac-12.

Defensive Line: Thin On Experience

Up the middle, however, lingering concerns still remain. While the linebacking corps appears poised to break through, the situation on the defensive line is much more precarious.

"[My] [b]iggest worry is probably the thinness a little bit at defensive line," Helton said at Pac-12 Media Days... "It kind of reminds me of -- remember when Damien and Viane and Toa Lobendahn were all true freshmen and I was an offensive coordinator looking out there going, oh, my God, we're playing three true freshmen here. It doesn't mean that they're not talented, they're just inexperienced."

Plus, outside of a guy who only managed to play two games for Utah last season, the Trojans don't have many weathered reinforcements behind their starters -- the defensive line reserves can boast just one junior and one senior. If none of these young reserves can step up, that could present a myriad of issues for an already inexperienced starting unit.

Fatigue could become an issue with just three healthy scholarship players to rotate in for presumptive nose tackle Noah Jefferson and defensive ends Malik Dorton and Rasheem Green. If any miss time or struggle, that could stretch out an already thin unit, forcing players to play tired, and likewise, at levels below their capability. It's a vicious cycle that increases injury risk, which could be devastating for a group that already likely lost Kenny Bigelow for the season.

Former four-star recruits, Green and Jefferson both played in every game last season and showed flashes of their potential. But talent alone might just not be enough -- they'll have to shoulder the brunt of the load, grow up, and prove themselves fast. Alabama's physical front comes knocking Week One, with Stanford's Tunnel Workers' Union coming two weeks later. Once more, they close a grueling season playing Oregon, Washington, UCLA, and Notre Dame, in that order. Yikes.

If defensive line coach Kenechi Udeze ends up blossoming into the "superstar" that Helton believes he can be, perhaps the line can be fine-tuned in time. If not, the defense could be on the field for a long time -- the Achilles heel in a Trojan war.