Four top-10 teams -- and nine ranked teams in all -- lost in week five of the 2021 college football season, and the wackiness and chaos levels are higher than they've been in years. As you would expect, week five's unpredictability has resulted in a lot of movement in the SP+ ratings. At the top, however, the top three remain the same: Georgia, Alabama, and a rapidly improving Ohio State lead the way, a few steps ahead of everyone else.
What is SP+? In a single sentence, it's a tempo- and opponent-adjusted measure of college football efficiency.