LAS VEGAS – It almost felt like LSU football tried to bluff its way into a season-opening victory in Las Vegas but USC called it in the final seconds.

The No. 12 Tigers (0-1) grabbed their first lead in the third quarter and tried to coast the rest of the way. The No. 23 Trojans (1-0) had other plans to escape Allegiant Stadium with all the chips and it did behind a 13-yard rushing touchdown from Woody Marks that gave USC the 27-20 win Sunday night.

Brian Kelly was animated and heated in his postgame press conference, calling out his team for "feeling like the game was over" when it led 17-14 in the fourth quarter.

Following LSU's fifth straight season-opening loss, here are three burning questions.

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Would wide receiver Chris Hilton have made a difference for LSU football vs USC?

LSU played without starting X receiver junior Chris Hilton (bone bruise). Hilton is more of a burner over the top for the offense, a guy that can stretch the field.

What's one thing that new offensive coordinator Joe Sloan and junior quarterback Garrett Nussmeier didn't do much against USC? Take deep shots. Nussmeier had two throws beyond 15 yards in the air, the longest a 41-yard completion to Aaron Anderson in the fourth quarter.

Had Hilton been healthy, it's reasonable to think Sloan would've dialed up more deep balls. USC played fairly close to the line of scrimmage for most of the game, which stymied the outside quick throws and check-downs from Nussmeier late.

How much improvement did we see from LSU's defense under Blake Baker?

The simple answer: A decent amount.

Senior defensive end Sai'vion Jones applied some pressure and had some batted balls. We got glimpses of what new defensive coordinator Blake Baker wants to do with Harold Perkins Jr. on third downs and obvious passing situations. Sophomore cornerback Ashton Stamps performed masterfully.

The truth is LSU's defense played with USC in front of it for most of the game. Before the fourth quarter, the Trojans had managed just 271 yards of offense. The problem was the offense stalled out, running only 15 plays in the fourth quarter, picking up two first downs to leave a work-in-progress defense on the field too long.

LSU kept a Lincoln Riley offense below 500 yards and allowed only three third-down conversions. All things considered, that should have fans encouraged.

Will LSU clean up the penalties or will that be a problem in 2024?

Kelly was rightly disappointed in LSU's lack of discipline. It had 10 penalties for 99 yards. What's most concerning is who committed them.

The Tigers' veterans and leaders racked up a lot of the damaging yards. Star junior left tackle Will Campbell had false starts to open drives out of media timeouts. Junior receiver Kyren Lacy imitated shooting a gun at USC senior cornerback Greedy Vance Jr. in celebration after scoring a touchdown and was hit with a 15-yard penalty.

Senior safety Major Burns was assessed an unsportsmanlike flag after the defense secured a stop in the fourth. Jardin Gilbert's targeting call set up USC's game-winning score.

LSU won't completely outclass most teams on its schedule. Helping those teams, as it did with USC, with field position and momentum shifts with the penalties, could put the Tigers in a precarious spot.

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Cory Diaz covers the LSU Tigers for The Daily Advertiser as part of the USA TODAY Network. Follow his Tigers coverage on Twitter: @ByCoryDiaz. Got questions regarding LSU athletics? Send them to Cory Diaz at bdiaz@gannett.com.

This article originally appeared on Lafayette Daily Advertiser: Most burning questions for LSU football after opening loss to USC