Here are the highest-graded players at every position from the 2020 season, plus the top rookie and a surprise from each position. Many of the top-graded players should come as no surprise, but there are several instances where the grades and the statistics or general perception of a player don't necessarily align. The quarterback position falls into the former category.
Best overall: Aaron Rodgers, Green Bay Packers
Regular-season PFF grade: 94.5
Rodgers came into this season with something to prove amid chatter that he was no longer a truly elite quarterback and the Packers' decision to spend their first-round pick on his eventual replacement -- Jordan Love -- rather than on another receiving option for Rodgers. But his MVP-caliber 2020 season served as a reminder that few quarterbacks occupy the same tier as he does when he's on top of his game. Rodgers' deep ball, in particular, delivered this season -- his 1,242 passing yards on passes thrown 20 or more yards downfield led the league.
Top rookie: Justin Herbert, Los Angeles Chargers
Herbert was the third quarterback to come off the board in the 2020 NFL draft, but he still exceeded expectations in his first season in Los Angeles. The most impressive aspect of his game was his ability to produce with defenders in his face. Only Russell Wilson was pressured on more dropbacks (251) than Herbert was (239), but no quarterback was better in those pressured situations. The Oregon product's 75.4 passing grade under pressure led all quarterbacks, as did his 99.4 passer rating on those plays.
Biggest surprise: Josh Allen, Buffalo Bills
The Allen who took the field in 2020 looked very different from the Allen who posted a 65.3 PFF grade across the 2018 and 2019 seasons combined. The work he put into changing his throwing mechanics in the offseason clearly paid dividends in the accuracy department. Per PFF's accuracy charting data, Allen went from throwing an uncatchable pass on 26% of his passes across his first two seasons -- the worst mark in the league -- to 16% during the 2020 regular season, fifth best in the NFL.