Pro Football Focus faces growing criticism from NFL players who question the analytics service's grading methodology, with former defensive ends Chris Long and J.J. Watt publicly condemning the system despite its widespread use across all 32 teams.

PFF assigns 0-100 grades to every player after dissecting game film play-by-play. The service delivers data to NFL teams by noon Monday, with grades calculated through multiple evaluators reviewing broadcast footage and all-22 film. NBC displays PFF rankings during Sunday Night Football, and news outlets regularly publish the grades.

San Francisco 49ers tight end Luke Farrell said he ignores PFF grades entirely. Fellow tight end Jake Tonges acknowledged the context-dependent nature of individual plays makes accurate grading difficult.

"There are so many moving parts to any play, especially a run play. It's really hard to break down and diagnose who did a bad job," Farrell said.

Long criticized PFF in October after the service ranked Patrick Mahomes as the league's 13th-best quarterback. Watt went further, stating that while PFF offers valuable data, the player grading component should be discontinued.

PFF evaluators assign marks ranging from negative-2 to positive-2 for each play based on execution rather than outcomes. Ben Stockwell, PFF's VP of data collection, emphasized grades reflect individual contribution independent of play results.

"We're evaluating how well someone has contributed to make that happen," Stockwell said.

Cris Collinsworth, who bought a majority stake in PFF in 2014 and serves as CEO, invited critics to tour the company's operations. Stockwell said PFF welcomes feedback from teams and uses it to refine the grading process.

Mac Jones offered a measured assessment, calling himself "kind of a nerd" about analytics but noting inconsistencies between his performance and assigned grades.