Defense wins championships.

This phrase may be cliché, but in the sports world, a solid defense almost seems like an afterthought — after all, you do need goals in soccer, runs in baseball or points in football to emerge victorious.

At USC, a star-studded offense overshadows a Trojan defense that has not been given enough credit for its play this season.

Taking flight · Sophomore linebacker Chris Galippo celebrates after the Trojans defense held off Notre Dame’s last-minute rally. Galippo anchors a defense that ranks fifth nationally, letting up only 11.7 points per game. - Dieuwertje Kast | Daily Trojan

The surplus of running backs at USC is always mentioned. True freshman quarterback Matt Barkley grabbed headlines after he was named the starter at the beginning of the season. Junior running back Joe McKnight and junior wide receiver Damian Williams are praised for their spectacular playmaking ability.

But what happened to the Trojans’ defense?

Other than senior safety Taylor Mays, this defense is largely unrecognized and perhaps underappreciated for its work so far this season.

After losing eight key players last year, it’s understandable to think that this would be a rebuilding year for the defense. But at USC, the plethora of talent is neverending.

Concerns over who would step in and fill those voids were raised prior to the start of the season. But the solid play of the new starters should put to rest any other doubts that may still be present.

Sophomore linebacker Chris Galippo is one of those players who has stepped in and played a significant role for the defense.

“He’s a terrific football player. He’s very bright and savvy and makes a lot of great decisions,” said USC coach Pete Carroll.

Galippo is the leading tackler for a team that is surrendering only 11.7 points per game, which ranks fifth nationally in scoring defense.

In addition to keeping opponents out of the end zone, the Trojans are holding opposing offenses to just 260 yards per game, which ranks ninth nationally in total defense. They are also only allowing 67.7 rushing yards, which ranks fourth nationally.

“These guys took the challenge that they wouldn’t allow this defense to take a step backwards because of the guys leaving,” Carroll said.

The backbone of last year’s defense was the core of linebackers that included Rey Maualuga, Brian Cushing, Clay Matthews and Kaluka Maiava. All four players moved onto the NFL and were arguably the best group of linebackers in college football history.

Last year, they anchored a defense that only allowed nine points per game, 221.7 yards per game and 87.4 rushing yards per game.

This year’s defense has held its own through the first six games of the season.

“They’ve played great football. They’ve played the run really well, taken care of the deep balls and the passing game is really difficult on our opponents,” Carroll said.

Prior to the contest versus Notre Dame last weekend, the USC defense had not allowed a touchdown through the air.

Galippo is healthy for the first time in his USC career. The former standout from Servite High School only played three games his freshman year because of to a herniated disc that required season-ending back surgery. In 2008, Galippo underwent another back surgery prior to the football season, but he served as the backup middle linebacker that season.

After undergoing two back surgeries, Galippo reflects on his time off from playing football.

“It made me work harder … and sitting behind guys like Rey, Cushing and guys like that, I learned a lot,” he said.

Now, he is getting an opportunity to showcase his abilities.

In the second game of the season versus then-No. 8 Ohio State, Galippo intercepted a pass thrown by quarterback Terrelle Pryor and returned it to the two-yard line. The interception set up the first touchdown of the game for the Trojans and the score proved critical in a game in which both offenses were stymied.

Meanwhile, it was the defense that would not budge and held Ohio State to three-and-outs. It was the defense that would not let Ohio State steal a victory. This defense was solid throughout the entire game and gave the offense a chance to win at the end.

Against Cal, the USC defense held Heisman-hopeful running back, junior running back Jahvid Best, to just 47 rushing yards on 14 carries. Not too bad considering Best was averaging almost seven yards per carry prior to the contest.

Even when the Trojans’ defense is not at its best, its resiliency and determination shine through.

This past weekend at Notre Dame was a huge test for the defense as it tried to slow down Heisman-candidate junior quarterback Jimmy Clausen and the electrifying junior wide receiver, Golden Tate.

Through the first three quarters, the Trojans continually pressured Clausen and shut down the Fighting Irish’s running game.

In the final quarter, Notre Dame cut the lead to a single touchdown. With nine seconds to play and the Fighting Irish at the USC four-yard line, the Trojans’ defense held strong in a goal line stand.

“We are much better this year than we were last year,” Mays said.

Now that Galippo is finally healthy, his contributions and stellar play have provided stability for the defensive unit. Playing for one of the top football programs in the nation, he said, “is something [he] always dreamed of” and it is no surprise that he is fulfilling, and perhaps exceeding, the expectations that heralded him a five-star recruit out of high school.

“He’s done a tremendous job and [the coaching staff] is pleased with the way he’s been developing,” said USC defensive coordinator Rocky Seto.

With Galippo in the middle anchoring the linebackers and Mays providing an experienced, imposing presence in the secondary, can the Trojans’ defense play any better?

“We’re still trying to get better and we’re still trying to improve,” Seto said.

So far, the defense has been nothing but rock solid.