Sunday was some of her best work yet.

On a festive day that blended Clark nostalgia with a massive matchup in the present, No. 22’s mere presence unlocked a winning route few outside the Iowa program thought was possible. Sunday’s final scene inside Carver-Hawkeye Arena marked another memorable moment in a recent run full of them, as Iowa secured a sizable signature win that spilled in perfectly to Clark’s postgame jersey retirement ceremony.

Not only did the Hawkeyes’ 76-69 win over JuJu Watkins and No. 4 USC inject confidence into a roster still hunting consistency across the board, it provided the perfect backdrop for Clark to officially pass the torch to Iowa’s next wave. On this day, Jan Jensen’s group embraced everything that arrived with Sunday’s incredible scene.

“Today was just amazing,” said senior point guard Lucy Olsen, who delivered a game-high 28 points punctuated by a riveting fourth quarter. “Everything Caitlin has done for the sport, that’s part of the reason I’m here — because of how much she’s grown women’s basketball.”

More: Leistikow: As Caitlin Clark’s No. 22 is retired, Iowa women’s basketball seizes seismic win

Even with all intangibles on the home side, Iowa’s on-court product had to match the arena aura. After coughing up a hefty lead early that led to tense action late, the Hawkeyes (15-7, 5-6 Big Ten Conference) needed to operate with the confidence Clark leaned on so much throughout her collegiate years.

Olsen took charge there, pouring in 15 points while going 5-for-5 at the line in the fourth quarter alone. A 63-57 advantage with five minutes remaining held up throughout a chaotic finish. Defensive intensity balanced out perfectly while forcing four USC turnovers over the final 10.

Watkins did all she could to keep the Trojans (19-2, 9-1) afloat, delivering 27 points on 8-for-22 shooting while standing as USC’s only reliable offensive option. But the cavalry never came to offer assistance. Meanwhile, the Hawkeyes picked up 13 points from Addi O’Grady, 11 more from Sydney Affolter and another 10 via Hannah Stuelke despite her sitting the entire fourth. All of the contributions added up to make this upset possible.

“It was really a huge part of our gameplan, focusing on our defense. Really making sure that JuJu was going to pass to other people and make other people hurt us,” O’Grady said. “Obviously, JuJu was going to get her own points but to not get discouraged by that. When she wasn’t hitting and no one was hitting, we were just rolling.”

Hear from Lucy Olsen, Addi O’Grady after Iowa women’s basketball upsets USC

Hear from Lucy Olsen, Addi O’Grady after Iowa women’s basketball upsets USC

It was clear early this could be a special afternoon. Iowa’s start at least was something from a basketball dream. USC missed just about everything it attempted, literally, while Iowa leaned on a bumping building with several eye-popping treys. A methodical 15-0 run saw the Hawkeyes up 17 before everyone had a chance to breathe.

USC’s opening sputters would’ve permanently damaged many. The Trojans finished the first quarter 1-for-14 from the field with zero field goals until the final 30 seconds, giving Iowa a window to establish separation and keep the environment intense.

The Hawkeyes held off a Trojan charge for some time … but not long enough to even enter the locker room ahead. Iowa’s disastrous second quarter undid almost all of its positive early work en route to a 29-28 intermission deficit. As USC cranked up the press, the Hawkeyes had little success breaking it. Eleven first-half turnovers evened the action and set the stage for a seesawing finish.

So many other times this season, Iowa has wilted when the spotlight intensifies. Several near-wins have morphed into painful stumbles on the backs of rough finishes that put this team’s flaws further under the microscope.

With Clark in the building, though, anything is truly possible. The Hawkeyes showed that in the most emphatic way Sunday.

“I was so happy they got this moment,” Jensen said, “because they’ve had so many go the other way. It’s a possession here, a possession there. I really challenged them at halftime. I said, ‘You know what? Not today. Not after everything you’ve been through.'”

Dargan Southard is a sports trending reporter and covers Iowa athletics for the Des Moines Register and HawkCentral.com. Email him at msouthard@gannett.com or follow him on Twitter at @Dargan_Southard.