Column: Defense flails and Trojans go from waltz to trudge in loss to Cardinal

The powder puffs obscuring the USC football season finally cleared Saturday night to reveal the Trojans’ true appearance.

Still hard to tell with those black eyes and busted nose.

A mirror was finally held up to one of the allegedly prettiest teams in college football and the reflection was flat ugly.

This wasn’t Arkansas State. This wasn’t Idaho. This was Stanford, and this was a street fight, and the Trojans simply couldn’t hit back enough in a stunning 41-31 loss to the Cardinal at a Coliseum that is echoing boos.

Stunning, because this was the Cardinal team that couldn’t even score a touchdown in an opening loss to Northwestern.

Boos, because the Trojans blew an 11-point lead and some offensive fireworks with a defense that was continually steamrollered by bland, overpowered by boring, and overwhelmed by a Cardinal offense that was just smart and strong enough to win.

This wasn’t as historic as the 2007 upset here by a 41-point underdog Cardinal, or as dramatic as the 2011 triple-overtime win here by the Andrew Luck Cardinal, but in some ways it was just as painful.

USC was ranked sixth. That’s gone. Steve Sarkisian had been flying under the radar after his Salute to Troy debacle. His target has returned. Pat Haden had retreated to the background after his questionable support of Sarkisian. The questions surrounding him probably will creep back.

Not all is lost, not even close. The Trojans season is not over, there are at least nine games and plenty of big chances for redemption remaining. Their Final Four hopes are not over, or did everyone already forget that on its way to winning the national title last year, Ohio State lost to Virginia Tech?

But this was their first big test of the season, and they flunked it pretty big, and the 2015 season now officially begins not in a waltz, but a trudge.

“Football is a humbling sport, from one week to the next, your emotions can go from high to low quickly,” said Sarkisian afterward.

The Trojans were indeed low as they sprinted off the Coliseum field immediately after the game while the Stanford players stuck around and took in their win.

USC’s disappointment had been building since it lost a 21-10, second-quarter lead and realized Stanford simply would not go away.

The Trojans offense would wow, then the Trojans defense would fold. JuJu Smith-Schuster would score on a breathtaking 54-yard pass, and the Trojans defense would fold. USC actually took a 28-24 lead early in the third quarter and had finally recaptured the momentum and, yeah, you guessed it, the Trojans’ defense folded.

The Cardinal “came ready to play like we knew they would,” said Sarkisian.

And the Trojans defense was as unprepared as everyone feared it would be.

Cody Kessler led the flashy Trojans offense to 427 yards, but been-there-forever senior Kevin Hogan led the Stanford offense to 474 yards.

The nifty Trojans running backs led a rushing attack worth 155 yards, but Stanford’s pesky Christian McCaffrey, who seemingly touched the ball on every play, gained 115 by himself.

“This one hurts, obviously,” said Kessler. “But this isn’t the final game. This is a long season. This could be a turning point in the season.”

Hopefully for the Trojans, that turning point will not be like Saturday’s turning point, when Stanford responded to USC’s lead with a 10-play, 77-yard drive to regain the lead for good with 4:55 left in the third quarter on — you guessed it — one of those typical one-yard Cardinal plunges by Remound Wright.

“They made some tough plays at critical moments that we didn’t,” said Sarkisian.

Perhaps the toughest play and most critical moment occurred on a third-and-seven situation for Stanford midway through the fourth quarter with the Cardinal holding a seven-point lead. Out of nowhere, Hogan found McCaffrey for a 19-yard screen pass that led to what became a clinching field goal.

Any last bit of effort by the Trojans was hurt by some of their eight penalties for 87 yards, by the inability of the runners to dominate inside as they did on the Trojans’ first series, and simply by the same lack of defensive focus that Trojans fans have seen before.

Remember the final dreadful moments of last season in Utah? This was two hours’ worth of that. Here’s guessing Sarkisian won’t be the only Trojans coach under increased heat. Justin Wilcox, the defensive coordinator, will probably also soon be coming under fire.

Everyone knew it would be tough to replace the likes of Leonard Williams and Hayes Pullard. But goodness, few thought it would be so hard that the Trojans would be flattened in their first Pac-12 game, their first tough game, their first step toward a potentially dream season become another bit of a nightmare.

“We have to clean some stuff up,” said Kessler.

Yeah, like the 2015 football season, and fast.

bill.plaschke@latimes.com

Twitter: @billplaschke