What happened: The new Week 4 college football rankings are set to arrive Sunday after Saturday's results reshaped the Top 25 picture. A change at No. 1 is expected, with broader movement likely throughout the poll.

Why it matters: The weekly rankings reset the national pecking order heading into the next slate and can quickly change the spotlight around contenders. In late September, even a one-week jump or drop can shift the tone of the season's early race.

What to watch: Watch the top spot first, then how far the shake-up extends behind it once the poll is released. The scale of the reshuffle will show whether this was a one-team swap or a wider reset.