It’s a heated and sometimes silly debate. Dallas Cowboys cornerback Trevon Diggs had a season for the ages in one respect. He snagged 11 interceptions, the most by an NFL player in 40 years. On the other hand, certain interested parties want to discount the importance of those takeaways because Diggs was often on the receiving end of completed passes for huge gains, allowing 16.8 yards per reception.
One of the industry’s leading (and more controversial) evaluation outlets, Pro Football Focus, falls on the side of the spectrum that claims Diggs’ performance in 2021 wasn’t special at all. They claim that Diggs, a Pro Bowl corner and First-team All-Pro, wasn’t one of the top corners in the league. Rather, his interception total was inflated because some of them were off of tips, others were thrown right to him. Their metric for grading corners on a -2 to +2 scale on each individual play shows that he was really the 36th-best corner in 2021, not a top-10 player as the Pro Bowl nod suggests, and certainly not a top-four player as the All-Pro selection warrants.
Where does the truth lie? I’m no data scientist, but I do know enough about crunching numbers that I wanted to at least start a conversation about finding a better way to evaluate cornerbacks than PFF’s method. Consider this a launch point. I think it’s based on firm enough footing in the analytical world.
Walk with me.