Xavier Rhodes among NFL's worst corners, and Mackensie Alexander is Vikings' best?

Pro Football Focus has become somewhat of a football statistics bible.

Just like any sacred text, though, that can mean two different things to those who read it: some treat it as the definitive final word on everything, while others believe it is more open to interpretation.

I tend to think of PFF in the second way. The various data produced by those who work for the site is generated by a thorough review of game film, which makes it more useful than a lot of other evaluations. But any grade is inherently subjective, particularly since each player’s assignment on every play can be complicated and known only to his team.

With that as a windup, there are some very interesting grades from PFF as they pertain to Vikings cornerbacks this season. This is only through two games — an exceedingly small sample size — but I think most of you would agree the grades deviate from what the eye test and overall narrative have suggested this season.

Out of 106 cornerbacks ranked at the moment (subscription required), four of them play for the Vikings. They go, in order: Mackensie Alexander, Terence Newman, Xavier Rhodes and Trae Waynes.

The two stunners in that mix: Alexander, at No. 29 overall with a very solid 79.1 rating, is the top Vikings corner. And Rhodes, with a dreadful 44.0 rating, is 81st out of 106.

Rhodes spent much of last season among the top 25 PFF corners, ranking 14th in a piece they wrote in late November. He was generally thought to have played well the first two games of this season, holding Michael Thomas in check in Week 1 against New Orleans and keeping Antonio Brown to five catches for 62 yards in Week 2 against Pittsburgh.

Yet Rhodes finds himself ranked barely ahead of Waynes, who is 87th out of 106 corners with a 42.9 rating (though he does have one of the best run-defense grades among corners).

Alexander, a second year corner who was enough of a question mark coming into this season that the Vikings made a late trade to add Tramaine Brock, finds himself ahead of even Newman — a PFF darling who finished in their top 10 last year. Newman is still a respectable 43rd this season with a rating of 74.8.

So is this just a case where a few plays have skewed the sample size (even if it’s hard to find those plays as they pertain to Rhodes)? Is it a case where film review is showing something we’re missing during games? Or is it a reason to be skeptical of PFF as the football bible?

It could be some combination of all three, but it bears watching as the season goes along if Rhodes and Waynes are the future of this secondary.