LOS ANGELES — Southern California head coach Clay Helton was describing how everything quarterback Sam Darnold did well in a loss at No. 9 Notre Dame was negated by turnovers when the lights suddenly went off during his news conference on Tuesday.

It’s been that kind of season for the Trojans, where just talking about turnovers can darken the mood.

Headed into a critical showdown at Arizona State on Saturday that could decide which team emerges from the Pac-12 South to play for the conference title, No. 21 USC knows it has to solve its turnover woes or see its once-promising season end in bitter disappointment.

“We stress it on a daily basis and hopefully it will pan out for us and that turnover bug will go away,” Helton said.

USC has now committed 19 turnovers in eight games, the most among Power 5 teams and tied for second-to-last among FBS teams. Darnold lost a fumble of USC’s first play from scrimmage against the Fighting Irish and later threw his 10th interception of the season, with both turnovers leading to touchdowns.

“It turned bad right away, and their offense is good,” left tackle Toa Lobendahn said of the 49-14 loss to Notre Dame. “We can’t shoot ourselves in the foot and then just have them score on us like that. It put us in a bad spot.”

Cornerback Jack Jones also muffed a punt, which Notre Dame recovered and turned into a touchdown.

The defense, which had thrived in limiting the damage from such sudden-change opportunities, has now allowed 35 points off turnovers in its last two games.

Darnold hoped the team would accept the comprehensive nature of the defeat and use it as a rallying point.

“But it’s up to the whole offense and for me to manage that, and for the defense to play better, and the special teams to play better. It’s up to the players, and I think if we take that mentality then we’ll be good moving forward,” Darnold said.

Helton and Darnold both agreed that the redshirt sophomore is doing a better job of taking what the defense is giving him. The only breakdown was against Notre Dame when Darnold got greedy and didn’t see a defensive back in coverage.

“I was trying to get all 21 points back in one play and can’t do that,” Darnold said.

Instead, Notre Dame went ahead 28-0 in the second quarter and never looked back.

The Sun Devils made the most of similar opportunities in their upset of No. 12 Washington and a resounding road win at Utah. A blocked punt set up Arizona State’s only touchdown against the Huskies, and four interceptions allowed Arizona State to grind down the Utes.

Darnold was able to bounce back from another turnover-plagued road loss last season to take down Arizona State 41-20 at home. That game sparked a nine-game winning streak that closed out the season.

USC needs those types of performances from Darnold over the next two weeks to gain potential tiebreakers over the surging Arizona schools.

“With us and Arizona and Arizona State up at the top of the South right now … you look at it as kind of a make-or-break situation,” Darnold said. “But at the same time, we’re going to take the same mentality that we take into every single game. But, yeah, we’re definitely aware of the circumstances, for sure.”

NOTES: Cornerback Iman Marshall sprained the MCL in his left knee against Notre Dame and did not practice. … Running back Stephen Carr saw his most extensive action in practice since injuring his foot at Washington State. … Outside linebacker Porter Gustin (toe/biceps) did some light running and is getting closer to returning, Helton said.


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