What happened: The NFL and NFL Players Association agreed that a third violation of the same safety rule will trigger a one-game suspension. The five categories are hip-drop tackles, horse-collar tackles, launching, hits on defenseless players and blindside blocks.

Why it matters: Each affected player remains three same-category violations away from a ban. In future seasons, two violations in one year will leave one strike carrying into the next.

What to watch: Players nearing the suspension threshold will meet with the NFL alongside their coaches. The first regular-season violations will establish the new system's initial strike counts.