NFL QB Rankings, Week 8: Brock Purdy, Patrick Mahomes and the 4 man race to be 2023’s best QB

Patrick Mahomes, Josh Allen, Tua Tagovailoa and Brock Purdy are locked in battle for the top spot.

Brock Purdy and Tua Tagovailoa backslid in Week 7. Now Patrick Mahomes has them in his sights.

The reigning MVP’s steady climb up the advanced stats rankings continued after a comfortable 14-point win over the Los Angeles Chargers Sunday. By leaning on Travis Kelce and Rashee Rice, Mahomes proved he’s still elite — and the numbers back it up.

He vaulted into third place in this week’s rankings thanks to a 424-yard, four touchdown performance — the fifth 400-yard, four-plus touchdown game of his career to date. Ahead of him lie Purdy and Josh Allen, two quarterbacks who failed to win as road favorites last week but turned in performances that, at the very least, looked decent on the stat sheet despite missed opportunities. With Tagovailoa close behind, these are the four players advanced stats suggest are frontrunners for this year’s MVP race.

Let’s talk about those numbers. Expected points added (EPA) is a concept that’s been around since 1970. It’s effectively a comparison between what an average quarterback could be expected to do on a certain down and what he actually did — and how it increased his team’s chances of scoring. The model we use comes from The Athletic’s Ben Baldwin and his RBSDM.com website, which is both wildly useful AND includes adjusted EPA, which accounts for defensive strength. It considers the impact of penalties and does not negatively impact passers for fumbles after a completion.

The other piece of the puzzle is completion percentage over expected (CPOE), which is pretty much what it sounds like. It’s a comparison of all the completions a quarterback would be expected to make versus the ones he actually did. Like EPA, it can veer into the negatives and higher is better. So if you chart all 33 primary quarterbacks — the ones who played at least 112 snaps in seven weeks — you get a chart that looks like this:

via RBSDM.com

Top right hand corner is good. Bottom left corner is bad. Try splitting those passers into tiers and you get an imperfect seven-layer system that looks like this:

via RBSDM.com and the author

These rankings are sorted by a composite of adjusted EPA and CPOE to better understand who has brought the most — and the least — value to their teams across the small sample size. It’s not a full exploration of a player’s value, but it’s a viable starting point. Let’s take a closer look.