BATON ROUGE — Brian Kelly and LSU football kicked off the 2024 season Sunday night in Las Vegas in a top-25 showdown.

And for the fifth straight season, the Tigers opened their season with a loss — this time letting a fourth-quarter lead slip away in the waning seconds to the Trojans — dropping the season opener, 27-20 inside Allegiant Stadium at the Vegas Kickoff Classic.

It was a tight game throughout. The lead between LSU and USC changed four times in the second half while the largest lead of the night was final 7-point margin in favor of the Trojans.

LSU entered the contest No. 12 in the USC LBM Coaches Poll and No. 13 in the Associated Press Poll. LSU remained in the Coaches poll after its season-opening loss to Florida State last year but Kelly's team was the preseason No. 5 team. Three seasons ago, the Tigers fell out of the rankings after dropping the opener at unranked UCLA.

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With LSU-USC being a top-25 matchup, were the Tigers able to remain inside the college football rankings?

LSU rankings update

LSU fell seven spots to No. 19 in the US LBM Coaches Poll and five spots in the AP Poll to No. 18 after the USC loss. The Tigers are the first winless team ranked in both polls and they're ranked ahead of teams like Kansas, North Carolina State, Louisville and Washington — who all won their opening games.

College football rankings, Week 2

US LBM Coaches Poll

1. Georgia (1-0)

2. Ohio State (1-0)

3. Texas (1-0)

4. Alabama (1-0)

5. Ole Miss (1-0)

6. Oregon (1-0)

7. Notre Dame (1-0)

8. Penn State (1-0)

9. Michigan (1-0)

10. Missouri (1-0)

11. Utah (1-0)

12. Tennessee (1-0)

13. Oklahoma (1-0)

14. USC (1-0)

15. Miami (1-0)

16. Kansas State (1-0)

17. Oklahoma State (1-0)

18. Arizona (1-0)

19. LSU (0-1)

20. Kansas (1-0)

21. Iowa (1-0)

22. Clemson (0-1)

23. North Carolina State (1-0)

24. Louisville (1-0)

25. Washington (1-0)

AP Top 25 Poll

1. Georgia (1-0)

2. Ohio State (1-0)

3. Texas (1-0)

4. Alabama (1-0)

5. Notre Dame (1-0)

6. Ole Miss (1-0)

7. Oregon (1-0)

8. Penn State (1-0)

9. Missouri (1-0)

10. Michigan (1-0)

11. Utah (1-0)

12. Miami (1-0)

13. USC (1-0)

14. Tennessee (1-0)

15. Oklahoma (1-0)

16. Oklahoma State (1-0)

17. Kansas State (1-0)

18. LSU (0-1)

19. Kansas (1-0)

20. Arizona (1-0)

21. Iowa (1-0)

22. Louisville (1-0)

23. Georgia Tech (2-0)

24. North Carolina State (1-0)

25. Clemson (0-1)

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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 rankings: Tigers down in updated college polls