It would have been difficult even under the best circumstances.
But USC traveled to the cold Midwest intent on shrugging off the firing of one coach and rallying around another.
The Trojans made big plays against No. 14 Notre Dame and fought back from a 14-point first-half deficit before succumbing to the surging Fighting Irish, 41-31, on Saturday night at Notre Dame Stadium.
Five days after Steve Sarkisian was fired as their coach — and offensive coordinator Clay Helton was installed as their interim leader for the second time in three seasons — the Trojans lost their second consecutive game and dropped to 3-3.
And it doesn’t get easier.
Next week the Trojans play No. 4 Utah and will be in danger of losing three games in a row for the first time since 2013.
“I told them with every fiber of my being, every fiber, that I truly believe this is a football team that can be great,” Helton said. “But we have to eliminate the mistakes.
“There’s no reason that we can’t go win the Pac-12 South. . . . I look forward to seeing the rest of the season, add ‘em up at the end, for this to be a good football team.”
USC players said the week of turmoil did not affect their performance.
“Not at all,” said Adoree’ Jackson, who scored on a long touchdown pass play but blamed himself for giving up several long passes on defense.
Safety Chris Hawkins said the Trojans were ready despite the events of the week.
“We’re a football team — we sign up for this,” he said. “When it happens, it happens. We had the right amount of preparation. I felt like we could have won this game.”
Notre Dame scored at least 40 points against the Trojans for the first time since 1977, when the Fighting Irish broke out their green jerseys and routed USC, 49-19.
No fashion changes were necessary Saturday.
Instead the Fighting Irish relied on quarterback DeShone Kizer and running back C.J. Prosise — both of whom began the season as backups and became starters after season-ending injuries suffered by starters.
Kizer passed for 227 yards and two touchdowns. Prosise rushed for 143 yards and two touchdowns. Receiver Will Fuller caught three passes for 131 yards, including a 75-yard touchdown on the Fighting Irish’s first play.
“Their skill is phenomenal,” Helton said of the Irish. “They did a great job of winning their one-on-one matchups, especially the deep ball.”
USC lost despite outgaining the Fighting Irish, 590-476.
The Trojans fell behind, 24-10, but came back with two big plays.
Receiver Jalen Greene connected with JuJu Smith-Schuster on an option pass that resulted in a 75-yard touchdown play, and Jackson turned a short pass into an 83-yard touchdown to pull the Trojans into a 24-24 tie at halftime.
The Trojans then took the lead on Cody Kessler’s short touchdown pass to tight end Taylor McNamara.
But in the fourth quarter, Notre Dame took advantage of two consecutive pass-interference penalties to set up a Prosise scoring run, and then used an option pass to set up Kizer’s touchdown pass to Corey Robinson.
“Some plays went their way,” Hawkins said, “and it seemed like we lost momentum late in the second half.”
Fighting Irish defensive back KeiVarae Russell clinched the victory with a spectacular interception on a deep Kessler pass. Max Redfield also intercepted a pass as the Fighting Irish improved to 6-1.
“USC is a great team with a lot of athletes on the field so you have to expect them to come out here and make plays,” said Notre Dame receiver Amir Carlisle, a transfer from USC who returned a blocked punt for a touchdown. “Their playmakers made plays but we . . . responded to adversity and just rallied together and were able to finish the game strong.”
Kessler, who struggled in a 17-12 loss to Washington, passed for 346 yards and two touchdowns, but he had two passes intercepted for the second consecutive game.
Kessler has had five passes intercepted in the last three games.
Follow Gary Klein on Twitter @latimesklein.
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