It all could have ended Saturday -- for that matter, it probably should have.

Any hopes of pushing for a College Football Playoff berth, of course, but also even hopes of winning the Pac-12 South.

This could have become a zombie season for USC after one game.

Instead, the Trojans scored two fourth-down touchdowns sandwiched around a recovered on-side kick in the span of 92 seconds, wiping out a 13-point deficit in the final minutes of the fourth quarter and undoing a morning full of mistakes and blunders to deliver a jolt -- and perhaps the proverbial wake-up call -- to a unique season that affords little to no margin for error.

Quarterback Kedon Slovis' 21-yard touchdown strike to Drake London on fourth-and-9 with 1:20 left might go down as the play of the season for this team and sent the Trojans to a momentous 28-27 win over Arizona State inside the Coliseum.

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Coach Clay Helton said he went up and down the sidelines predicting that very outcome to his players through that tense fourth quarter, but really, who could have seen this coming?

USC had lost three fumbles (one at the goal line), thrown a red zone interception, come up short on two failed fourth-and-1s and endured a couple back-breaking defensive lapses to allow Sun Devils quarterback Jayden Daniels the entire middle of the field to scramble for costly third-down conversions.

And the last turnover seemed to seal it as running back Markese Stepp fumbled at the Arizona State 23 with 6:04 left, ending what figured to be a crucially pivotal possession with the Trojans trailing 27-14. With about 3 minutes remaining, ESPN calculated that Arizona State had a 99.8 percent chance of winning.

"I tried to stay positive. When it was 27-14 I was going up and down the sidelines saying, 'Guys, I'm looking at it right now, you're going to win this game 28-27. It's going to take two scores, we're going to have to treat it like a two-minute drive, go to our two-minute drive rules, we're going to get a touchdown, get an onside kick and go score again,'" Helton said afterward. "And they did it. I thought the whole sideline stayed positive, didn't panic, stayed poised and just really played situational mastery football the whole way."

Well, not the whole way certainly, but for those final six minutes at least.

Veteran defensive tackle Marlon Tuipulotu pulled Daniels down for a 2-yard loss on third-and-9 to force a quick Arizona State punt four plays after Stepp's fumble, and USC took over at its own 20-yard line with 4:28 remaining.

Almost immediately, the Trojans found themselves facing a fourth-and-3, but Kedon Slovis connected with Tyler Vaughns for a 14-yard pickup. Slovis then found Amon-Ra St. Brown open down the middle for 36 yards. But before long it was fourth-and-13 and the Trojans' hopes were on life support yet again.

USC managed to draw Arizona State offside, setting up a free play, and Slovis lofted the ball into the end zone to a decently covered St. Brown. It deflected off his hands -- apparently by intention -- and into the hands of redshirt freshman Bru McCoy, who was playing his first game with the Trojans.

"Really, we got them to jump offsides so at that point I just want to give them a chance. I know we're going to get another shot, it doesn't really matter if they pick it off so I threw it to Amon-Ra to give him a chance and he tips it up to Bru," Slovis said.

Said McCoy: "We called a freeze play, so we didn’t even have a play called at the time, but they just jumped offsides, so we ran verts. Amon-Ra did a great job just being aware. He realized it was a free play, so since it’s a free play, might as well give an opportunity to somebody. So he tipped the ball up, just was situationally aware, and I was able to make a play."

Arizona State 27, USC 21

With just 2:52 on the clock, the Trojans dialed up an on-side kick with freshman kicker Parker Lewis. It caromed off an unidentified Sun Devil and McCoy again found himself in the right place for another huge play, recovering the loose ball.

"I’d never repped an onside. They told me on the sideline that I was going to be the one running down for the onside,” McCoy said. "Honestly, I thought I messed up. I thought I could attack the ball. I was kind of waiting for that big one to jump up and go get it, but it stayed low. It kind of fell inside and I was staring at the ball the whole time, and I was able to fall on it."

That left 2:49 for yet a little more magic as USC took over at its own 45.

Redshirt senior running back Vavae Malepeai, who had fumbled at the goal line in the first quarter setting an ominous tone for the game while seeing his playing time cut significantly thereafter, earned some redemption with back-to-back runs of 20 and 13 yards to start the Trojans' final drive.

But yet again, USC would end up in fourth-and-long -- with a 5-yard false start pushing it to fourth-and-9 from the ASU 21 -- with its season effectively on the line.

In a six-game pandemic-shortened regular season where it’s already going to be an uphill climb to earn CFP consideration against conferences playing more games, all it takes is one loss this year to undo months of anticipation and goal-setting, and any oddsmaker would have penciled the Trojans in for theirs at almost any point of that fourth quarter Saturday.

So with all of that at stake, offensive coordinator Graham Harrell went to a play the Trojans had used frequently Saturday, but one that had rarely offered a good look downfield.

"That play's a play that we run all the time. We ran it a lot down the stretch there too, and to be honest with you they kind of dropped a lot of guys most times we ran it and they didn't give us a chance to get those down-the-field shots," Slovis said.

The play call wasn't for London specifically, but it was fitting that the standout sophomore ended up as the best read as he darted up the seam. London had been the one consistent for USC all afternoon and now the game was about to be in his hands -- literally.

"To be honest, anyone could’ve beaten them on that play. It was just the way they played it," London said.

Slovis took a quick drop and fired down the middle and into the end zone. There were two defenders in front of London, but the throw was perfect -- a 21-yard touchdown on 4th-and-9 after everything else that already had to occur to even make that moment possible.

"As good a pitch and catch as I've seen on the fourth down with Drake and 9. Just being a year older, that's one of those that you've got to pull the trigger -- if you hesitate at all it's not going to be a touchdown. And Kedon got that ball in there perfect timing and perfect accuracy," Helton said.

Said London, who finished with a team-high 8 catches for 125 yards and that TD: "The backer pushed out to me, there was no safety over top and the rest is history."

It might be if this season turns into anything for USC, because the Trojans shouldn't have been the team celebrating Saturday. Not based on the astronomical odds that existed with a little more than 6 minutes remaining.

"I told the guys in the locker room, this is one of those games I don't care how old I get, I'll never forget this game," Helton said. "I'll never forget this team for all the things that they've dealt with in 2020 and the fighters that they are and the competitive people that they are."

Amazingly, USC is now in the driver's seat in the Pac-12 South with a head-to-head win over an Arizona State team that might be the top challenger in the division, depending on what Utah shows this season.

Incredibly, the Trojans might have left the Coliseum with a charge of momentum despite everything that set up those dramatic final minutes.

Ultimately, this was not an ending of any sort for this team's 2020 hopes -- it might just be the beginning.

The Trojans have a lot of questions to solve. The offensive line was worrisome, even before starting center Brett Neilon hobbled off the field late in the game. The turnovers were troubling, obviously. The vaunted passing attack was muted for much of the night, even if Slovis ended up 40-of-55 for 381 yards, 2 TDs and 1 INT in the end. And the defense gave up 258 rushing yards, including 111 to Daniels.

But USC will get a chance to try to address all those matters because officially they haven't taken any toll yet.

"For the chips to fall the way they did, having the amount of turnovers we had, and still being able to come up with the W, it says a lot about the character of this team and how we’ll play moving forward," McCoy said.

Said Helton: “A year ago we may not have won this game.”

He better hope a week from now his Trojans don’t try to follow a similar script, because this was one of a kind — a second chance in a season that didn’t figure to provide any.