What happened: QBI measures quarterback value per play across passes, rushes, scrambles, sacks and turnovers. Its model adjusts for opponents, protection, receiver quality, drops, yards after catch and pressure arriving within 2.5 seconds.

Why it matters: The forward-looking measure combines play-by-play analytics with PFF grades to account for elements conventional statistics miss. Twenty years of quarterback performance underpin its historical baseline.

What to watch: Updated QBI standings will appear each Tuesday during the season in a weekly quarterback stock report.