After grading every player on every play over the course of the regular season, the Pro Football Focus analysis team has identified the most improved in several categories, from second-year players on both sides of the ball to overall passer and many more:
Second-year player on offense
Melvin Gordon, RB, San Diego Chargers
Gordon struggled as a rookie in 2015. He averaged 3.5 yards per carry, ended with less than 500 total rushing yards and fumbled six times in 184 carries. Though Gordon still averaged less than 4.0 yards per carry this season (3.9), he gained 2.5 of them after contact (up from 2.2 as a rookie), scored 10 times and put the ball on the ground only twice, with 70 more carries (254).
Runner-up: Amari Cooper, WR, Oakland Raiders
Second-year player on defense
Landon Collins, S, New York Giants
As a rookie, Collins played 56.0 percent of his snaps lined up deep in the secondary as a free safety, and it was ugly. But in his second season, he was there on 36.7 percent of his snaps, and he was used far more as a box weapon. His 46 defensive stops are eight more than the next-best safety, and he either picked off or broke up 10 passes.
Runner-up: Markus Golden, OLB, Arizona Cardinals