BATON ROUGE — The calendar flips to September on Sunday and LSU football officially flips its calendar to football season.

The No. 12-ranked Tigers will take on No. 23 USC in the Vegas Kickoff Classic on Sunday at Allegiant Stadium in Las Vegas (6:30 p.m. CT, ABC).

Here's what to know about the season-opening contest:

Garrett Nussmeier era kicks off for LSU football

LSU's offense will have a much different look this season. Not only is Joe Sloan taking over at offensive coordinator, but the Tigers said goodbye to Heisman Trophy-winning quarterback Jayden Daniels.

Junior Garrett Nussmeier now assumes the reins as the Tigers' starting quarterback. He started the ReliaQuest Bowl for LSU in January and performed well, going 31 of 45 for 395 yards, three touchdowns and one interception.

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LSU head coach Brian Kelly said this preseason he's excited to see how Nussmeier play now that "he's got the keys to the offense.

"Having a quarterback that has been in the system for the last couple of years, that knows what it looks like, what it's like to be in an SEC battle and has played in a game against a pretty darn good defense, those things make you feel a little bit more at ease going into these games," Kelly said earlier this week.

What to know about USC Trojans

Any team coached by Lincoln Riley will be known for its offensive prowess. USC did lose a Heisman Trophy-winning quarterback itself in Caleb Williams and it's now the Miller Moss ear for the Trojans. Moss also started USC's bowl game last season, leading the Trojans to a 42-28 win over Louisville in the Holiday Bowl when he went 23 of 33 for 372 yards, six TDs and one pick.

The biggest question around USC is on the defensive side of the ball. There's a multitude of new faces as nine transfers came into the program as well as this is defensive coordinator D'Anton Lynn's first season at USC, coming over from UCLA. It appears at least four new players will start for the Trojans on defense.

Kelly said earlier this week that with the turnover on USC's defense, the staff has had to watch more UCLA tape than USC to try and get a grasp of what the Trojans could do structurally.

Will Blake Baker's debut as LSU DC be encouraging?

Last season was a historically bad performance on the defensive side of the ball for LSU and Kelly overhauled the staff. He hired an all new defensive staff, headed by new coordinator Blake Baker, who led Missouri last season to one of its best seasons in program history.

There's been some shuffling around, like with star linebacker Harold Perkins at the Will spot and Sage Ryan now at corner. Depth is a concern up front along the defensive line.

How will the Tigers look in their first game with Baker calling the defense?

LSU football vs. USC score prediction

LSU 24, USC 21: There's won't be as many points as most Vegas lines are predicting as this will be an ugly game with both teams committing mistakes with turnovers. LSU gets just enough stops on defense to edge out USC for its first season-opening win since 2019.

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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: LSU football vs. USC: Score prediction, scouting report