USC makes it four in a row with narrow win at Colorado

USC receiver JuJu Smith-Schuster frolicked on the field shirtless before the Trojans played Colorado on Friday night at Folsom Field.

The symbolic display during warmups was an opportunity to show teammates that nothing — not cold weather, not a victory-starved opponent, not even the Trojans’ miscues or penchant for putting themselves in a hole — should keep them reaching the final stretch of the season with a chance to win a title.

That stretch is finally upon them.

USC will enter it on a winning streak — if not exactly a roll — after a 27-24 comeback victory that kept the Trojans in the hunt for the Pac-12 South Division title heading into next week’s game at Oregon.

Cody Kessler passed for three touchdowns and the defense and special teams came up with several big second-half plays as the Trojans held off the Buffaloes and improved to 7-3 overall and 5-2 in Pac-12 play.

“If you had said at the beginning of the year that you would have an opportunity to win the Pac-12 South with two games left — that’s where you want to be,” interim Coach Clay Helton said.

After a loss at Notre Dame, Helton has led the Trojans to victories over previously unbeaten Utah, California, Arizona and Colorado. His bid for the permanent position could be decided in Eugene and at the Coliseum against UCLA.

A possible USC championship run still requires some help in the form of a Utah loss.

And the Trojans can help themselves by avoiding the slow starts that put them in a 14-3 hole two weeks in a row.

“I guess we just like giving Coach Helton a heart attack,” Kessler joked.

A defense led by lineman Delvon Simmons knocked Colorado quarterback Sefo Liufau out of the game and held off a Buffaloes team that has only one Pac-12 victory.

Simmons forced a fumble, blocked a field-goal attempt and had two tackles for loss, including a sack. For the second game in a row, the defense recorded 10 tackles for losses, including six sacks.

“It just clicked,” Simmons said of the defense’s second-half effort.

Helton praised his players’ poise and resiliency.

1/15

USC running back Ronald Jones II tries to evade Colorado linebacker Grant Watanabe in the first half of their game Friday night in Boulder.

  (David Zalubowski / Associated Press)

2/15

Trojans quarterback Cody Kessler unleashes a pass against the Buffaloes in the first half on Nov. 13.

  (Justin Edmonds / Getty Images)

3/15

Colorado running back Patrick Carr is dragged down for a loss by USC safety John Plattenburg in the first half.

  (David Zalubowski / Associated Press)

4/15

Buffaloes defensive end Jimmie Gilbert sacks Trojans quarterback Cody Kessler in the first half.

  (Justin Edmonds / Getty Images)

5/15

USC running back Justin Davis leaps over the line for a three-yard gain in the first half.

  (Justin Edmonds / Getty Images)

6/15

Colorado quarterback Sefo Liufau unloads a pass against USC in the first half. Liufau would leave the game later because of an injury.

  (Justin Edmonds / Getty Images)

7/15

Trojans running back Ronald Jones II picks up yards against the Buffaloes in the first half on Nov. 13.

  (Justin Edmonds / Getty Images)

8/15

Trojans linebacker Su’a Cravens sacks Buffaloes quarterback Cade Apsay during the first half.

  (David Zalubowski / Associated Press)

9/15

USC running back Justin Davis is stopped by Colorado linebacker Rick Gamboa after a gain in the second half of a Nov 13 game in Boulder, Colo.

  (David Zalubowski / Associated Press)

10/15

USC fullback Jahleel Pinner (38) celebrates his touchdown catch against Colorado with offensive tackle Chad Wheeler in the second half.

  (David Zalubowski / Associated Press)

11/15

USC quarterback Cody Kessler is hit by Colorado defensive back Chidobe Awuzie as he throws a pass in the third quarter Saturday.

  (Justin Edmonds / Getty Images)

12/15

Trojans defensive tackle Antwaun Woods recovers a Buffaloes fumble in the third quarter.

  (Justin Edmonds / Getty Images)

13/15

USC linebacker Uchenna Nwosu (42) signals the Trojans recovered a fumble by Colorado in the second half.

  (David Zalubowski / Associated Press)

14/15

USC wide receiver JuJu Smith-Schuster catches a touchdown against Colorado defensive back Tedric Thompson in the fourth quarter Friday night in Boulder.

  (Justin Edmonds / Getty Images)

15/15

Trojans wide receiver JuJu Smith-Schuster leads fans in song after USC defeated Colorado, 27-24, on Friday night.

  (David Zalubowski / Associated Press)

But he and his players know that the pattern they have followed the last few weeks will doom them against high-scoring Oregon.

“You can’t do that every week or you’re going to lose a ballgame,” Helton said, “So we have to find a way to fix it.”

USC trailed 17-6 at halftime before turning up its rushing attack and converting a turnover into a touchdown.

The Trojans put the ball in the hands of tailbacks Justin Davis and Ronald Jones II 11 times in a 13-play drive that culminated with Kessler’s touchdown pass to fullback Jahleel Pinner, only his third catch of the season.

Simmons forced a fumble on the first play of the ensuing possession and nose tackle Antwaun Woods recovered.

Kessler put the Trojans ahead for the first time since early in the game with a short touchdown pass to tight end Taylor McNamara.

Adoree’ Jackson blocked a long field-goal attempt to set up Kessler’s 36-yard touchdown pass to Smith-Schuster for a 27-17 lead that appeared to put the Trojans firmly in control.

But Nelson Spruce’s long punt return set up a short touchdown pass from backup quarterback Cade Apsay to fullback George Frazier to pull the Buffaloes to within 27-24 with about six minutes left.

USC could do nothing with its next possession, so it was on the Trojans’ defense for a final stop.

Colorado’s final possession ended when a fourth-down pass fell incomplete, enabling the Trojans to run out the final two minutes for the victory.

Helton will spend the week looking for ways to keep the Trojans playing like they have in the second half.

“We need to bottle that up and put it in the first half,” Helton said, adding, “We just need to put together four quarters of consistent football.”

gary.klein@latimes.com

Twitter: @latimesklein