Personnel Preview: USC Defense beat writer Dan Greenspan offers a preview of the Trojans defensive starters and key reserves.

Note: The following was provided to IrishEyes courtesy Dan Greenspan of

USC Front Seven

Despite limited depth, the Trojans have fared reasonably well against the run this season. The issue has been the lack of impact plays, especially from the linebackers. The starting trio, including both middle linebackers, has just 4 forced fumbles, 2 interceptions and 1 fumble recovery.

Left End #94 Armond Armstead – At nearly 300 pounds, Armstead gives the Trojans unmatched size along the line. But with so many Pac-10 teams going to some form of the spread, the junior's impact has been largely muted this season. Still, USC coach Lane Kiffin compares Armstead to Michael Strahan and believes he has a big future at the next level.

Left Tackle #98 DaJohn Harris – Written off by the previous regime, Harris was salvaged by legendary defensive line coach Ed Orgeron in the spring and shockingly ended up in the starting lineup. When he wants to, Harris can be as disruptive as any USC lineman, as demonstrated by his 3.5 sacks this season.

Right Tackle #91 Jurrell Casey – A mammoth presence in the Patterson/Ellis mold, Casey has 10 tackles for loss and 4.5 sacks, both totals tops among Trojans. The junior out of legendary Long Beach (Calif.) Poly seems like a lock to be drafted in the first round if he comes out after this year.

Right End #8 Nick Perry – Limited all season long by an ankle injury, Perry is still an elite pass rusher with 11 career sacks. The redshirt sophomore will rotate with Wes Horton, giving the Trojans three starting-caliber options at end.

Strongside Linebacker #17 Michael Morgan – Morgan has struggled this season despite his prototypical NFL athleticism. If the redshirt senior shows up versus Notre Dame, the USC defense might actually resemble the fearsome units Pete Carroll used to deploy.

Middle Linebacker #54 Chris Galippo – Since entering the starting lineup three weeks ago, the USC defense has really settled down with the steady Galippo leading the way. He suffered a concussion early at Oregon State, but should be good to go against the Irish. Galippo is also a special teams demon, anchoring most units under new coordinator John Baxter.

Weakside Linebacker #6 Malcolm Smith – After a slow start, Steve's younger brother has turned it on since returning from a knee injury. Smith has 7 tackles in each of his last three games with 2.5 tackles for loss, forced a critical fumble at Arizona and returned an interception 74 yards for a touchdown against Arizona State.

USC Secondary

Historically bad, that's the only way to describe the Trojans pass defense in 2010, allowing 272 yards per game. USC ranks 114 in the nation and dead last in the Pac-10. If there's one saving grace, it's that they'll get their noses dirty in the run game.

Cornerback #24 Shareece Wright – Although a senior, Wright entered this year with just three career starts because of injury and academics. Finally on the field, Wright is fearless and aggressive with 8 pass breakups, 7 tackles for loss, 2 forced fumbles and 2 fumbles recovered. Like the rest of his counterparts, however, he has often struggled in coverage.

Strong Safety #27 Marshall Jones – Part of the celebrated Westlake Village (Calif.) Oaks Christian senior class that included Jimmy Clausen and Marc Tyler, Jones' college career has been largely derailed by injuries. Finally healthy, the redshirt senior has played well as a starter the last two weeks and seems to be a major steadying force.

Free Safety #7 T.J. McDonald – Certainly his father's son – Tim was a six-time Pro Bowl selection and a Super Bowl winner – the sophomore leads USC in tackles by 18 tackles and is tied for the team-lead in interceptions. McDonald is often used as the eighth man in the box against the run.

Cornerback #37 Nickell Robey – After a trial by fire early, the true freshman has emerged as a cornerstone of the Trojan defensive backfield with 3 interceptions. Don't be fooled by his listed height of five-foot-seven, as Robey's athleticism will allow him to challenge anyone, even massive Michael Floyd. Robey usually plays the slot when USC deploys nickel personnel.

Key Reserves

Defensive End #96 Wes Horton – Splitting time with Perry, Horton was the team's top end before a back injury sidelined him for three midseason games. Still, he has 4 sacks, second-best for USC, and is very sound against the run.

Linebacker #42 Devon Kennard – The touted prep defensive end still seems like a strange choice for a move to middle linebacker, but did play extremely well in relief of Galippo against the Beavers with 8 tackles and 1.5 for loss. Kennard started the first eight games of the season before ceding his spot as a starter to Galippo.

Safety #29 Jawanza Starling – Starling started the first nine games of the season, but his job was in jeopardy even before he suffered a hamstring injury that kept him from playing at Arizona and Oregon State. Still, with such limited numbers, having the sophomore dressed and available would be a boost to the beleaguered secondary. Top Stories