LSU is a consensus 29.5-point home underdog to the Crimson Tide. The line had grown to -30 at William Hill sportsbooks in Mississippi.
Auburn, in 2011, is the only other team to be a 20-plus-point underdog in a game the season after winning the national championship, according to ESPN Stats & Information. The Tigers failed to cover in three such instances that season, versus Alabama, LSU and Georgia.
LSU put together one of the most dominant runs ever last season. Led by Heisman Trophy-winning quarterback Joe Burrow, the Tigers beat seven top-10 teams and boasted an overall margin of victory of 27 points en route to capturing the national championship.
It has been a precipitous fall for LSU this season, with Burrow and many of teammates from last year's squad now in the NFL. The Tigers are 3-4 with losses to Mississippi State, Missouri, Auburn and Texas A&M. Now, they face No. 1 Alabama in Baton Rouge as massive home underdogs.
In 1991, LSU was a 28-point home underdog to top-ranked Florida State. This week's point spread is poised to eclipse that high mark for the Tigers.
Alabama, on the other hand, heads to LSU having been the betting favorite in a record 74 consecutive games. The Crimson Tide were five-point favorites over LSU last season. The Tigers won 46-41.
ESPN Stats & Information researchers Bryan Beasley and Bryan Larson contributed to this article.