The game that really started the Alabama dynasty that has lasted a decade now was the 2008 season opener between Alabama and Clemson. Alabama took a highly hyped recruiting class (including Julio Jones) and dismantled the highly favored Clemson. This game represented a power shift in college football, and put Alabama on the national media lists for good.
Here’s a video from Al.com with some sound bytes from different people involved with that game, such as Terry Bowden, Rashan Johnson, and John Parker Wilson.
BOL: Same thing happened in 2017.