New helmets, old questions for Trojans going into Colorado game

USC will debut an alternate helmet Saturday against Colorado, which should provide plenty of fodder for debate among Trojans traditionalists and fashion-forward-thinking fans.

But will the shinier, new-look Trojans be any different than the ones that produced a 4-2 record in the first half of the season?

That is one of the main questions Coach Steve Sarkisian and No. 22 USC will answer when they play an improved — but 21-point underdog — Colorado team at the Coliseum.

“I really feel like we’re making progress,” Sarkisian said. “I feel like we’re getting better, which is exactly where you’d like to be halfway through the year.”

Better is a relative term for those who watched USC collapse against Arizona State and then barely hold on for a victory at Arizona.

But USC has a 3-1 record in Pac-12 Conference games and remains in contention for the South Division title. Colorado is 2-4 overall, 0-3 in conference play.

Most of the talk this week — much of it fueled, unprompted, by Sarkisian — concerned quarterback Cody Kessler’s need to throw longer passes that would result in more “explosive” plays.

“That’s a big point of emphasis for us right now,” offensive coordinator Clay Helton, “his trust in receivers to do the right thing.”

Kessler, who has passed for 11 touchdowns, with one interception, said he was not hesitant to throw longer routes.

Colorado’s young defense might be a good test case.

Former Trojans quarterback Matt Barkley passed for 12 of his school-record 116 touchdown passes against Colorado.

Second-year Coach Mike MacIntyre appears to have the Buffaloes on the upswing, but the Trojans are expected to once again test Colorado’s secondary.

Last season, Kessler passed for 184 yards and two touchdowns in a 47-29 victory over Colorado at Boulder.

But this season the Trojans have been largely unable to close out opponents in the fourth quarter.

USC’s defense gave up three touchdowns in the last four minutes against Arizona State, but the offense also contributed to the meltdown by failing to sustain drives.

It happened again last week against Arizona. The Trojans went conservative and nearly blew a 15-point lead, escaping with the victory only after Arizona missed a field-goal attempt.

“We’ve got to put more points on the board,” Kessler said, “and when it gets to the fourth quarter be more efficient.”

USC’s defense also must be better down the stretch.

If not for lineman Leonard Williams’ tackle on a two-point conversion attempt and Arizona’s inability to convert two field-goal tries, Sarkisian and USC would be in crisis.

Defensive coordinator Justin Wilcox said this week that the Trojans would use more players to keep the top 11 physically sound for the final minutes.

Cornerback Adoree’ Jackson left last week’s game because of a hip-flexor injury and cornerback Kevon Seymour left because of a stomach ailment.

Both are expected to return against Colorado, which features receiver Nelson Spruce, a former Westlake High standout who leads major college football in receptions at 10.3 a game.

“We have to do a better job of finishing,” Seymour said of the Trojans’ pass defense. “That’s our big thing — and other teams can see that too.

“We’re in position and we’re just not finishing on the ball. So once we get that down pat, we’ll be pretty good.”

Saturday would be a good time to start.

Visiting teams are 15-4 in Pac-12 games this season. In its last two games, Colorado has been close, losing to California, 59-56, in double overtime, and to Oregon State, 36-31.

“We have really improved,” MacIntyre said. “We just haven’t got over the hump in a couple games.”

gary.klein@latimes.com

Twitter: @latimesklein