LINKEDINCOMMENTMORE

Pro Football Focus uses a complex system to analyze every NFL player involved in every snap in every game and assigns a grade based on how he performed on that play, with each position having its own set of grading guidelines. Plus/minus scores are given in 0.5 increments and a small normalization factor is applied to make 0.0 the average grade for a game or season. To learn more, visitwww.profootballfocus.com

The Vikings have an elite player at all three levels of their defense, a major reason they are riding a five-game winning streak and leading the NFC North.

Nose tackle Linval Joseph is ranked second in the NFL at his position in PFF’s overall grades. Outside linebacker Anthony Barr ranks first at his position and safety Harrison Smith ranks second at his.

The Packers are hoping to revive their ground game, but they’ll find tough going up the middle against Joseph, whose outstanding +35.0 grade at the defensive tackle position (which is second only to the Rams’ Aaron Donald at +41.9) includes a +23.6 rating against the run (which is second only to the Ravens’ Brandon J. Williams at +26.3). Joseph’s 22 “stops” (solo tackles that result in an offensive failure) rank fourth in the league at that position.

Barr’s league-best +14.3 grade at outside linebacker includes a +6.9 pass-rushing grade, second only to the Patriots’ Dont’a Hightower (+8.2) at the position. Barr has been credited with 13 quarterback hurries, five quarterback hits and two sacks.

Smith’s overall grade of +15.0 at safety is second only to the Eagles’ Malcolm Jenkins (+16.9). The former Notre Dame star remains a sure tackler, which is crucial at his position. Smith has missed only three tackles and has allowed no touchdowns in his coverage. Smith excels at blitzing: The Vikings have had him blitzing on 7.7% of their pass plays, and with five quarterback hits, four hurries and one sack, Smith leads all NFL safeties with a pass-rushing productivity rating of +28.7.