What happened: Belichick had been away from the program on medical leave since early August after Bill Belichick called it a medical situation and declined further comment. ESPN's Pete Thamel reported Thursday that Steve Belichick resigned from the North Carolina staff.

Why it matters: North Carolina now has to reshuffle its defensive operation weeks into the season after losing the coach in charge of that unit. The departure adds to the instability around the program as the investigation continues beyond Michael Lombardi's exit earlier this month.

What to watch: North Carolina's next staff update should clarify who handles defensive duties going forward. Further school comment on the resignation and the wider investigation will show whether more changes are coming.