Poor starts to a young player's career or a cold stretches from an otherwise reliable veteran don't necessarily signal the beginning of the end. Players can always improve from year to year, and these 32 players — one for each team — improved the most from 2018 to 2019.
[Editor's note: Available to all of PFF's EDGE and ELITE subscribers, PFF's Free Agent Rankings Page consists of three-year grades, PFF WAR and in-depth analysis for all of the top NFL free agents. Contract information from our friends at Over The Cap is also available.