Steelers Week 4: David Johnson, Cameron Heyward given top grades by Pro Football Focus

Steelers tight end David Johnson looked like a man reborn on a quick flare pass down the sideline. He managed to evade two Vikings defender, including linebacker Chad Greenway, who feasted on Steelers offensive players all game. It went for a gain of eight, but it seemed like so much more. One of the few catches he's made this season, but it was without question his best performance to date.

That's something Johnson can say after each game this year, becoming one of the few Steelers players showing marked improvement with each game. Johnson received a very strong +4.2 grade for his efforts in Week 4, an amazing mark, considering he only played 24 snaps. That basically means he dominated on the vast majority of plays he was on the field.

The strength of it came in his run blocking. The Steelers are an improving running team, and Johnson's rise is a big part of it. This team went from having zero tight ends to two in the first four weeks of the season. They should be even stronger after their bye week.

It was a stark contrast on the defensive side of the ball. For all the hoopla continuously given to linebacker Vince Williams (and it's really not clear why he's earned the praise he has), he was savaged by the Vikings, and PFF, who gave him a -4.3 grade, with two missed tackles.

Just like the Steelers' problems replacing talented players with nothing at the tight end position, they're doing the same thing at inside linebacker, and it's dragging a lot of the defense down. Not that it's all on Williams - PFF gave the Steelers 17 missed tackles in the loss.

Defensive end Cameron Heyward (+1.9) had the highest grade for a defensive unit that, not surprisingly, did not grade out very well. Cornerback Ike Taylor (+1.8) joined Heyward as the only defensive players with positive grades.

Left tackle Mike Adams earned a -3.9, his third consecutive game with a negative rating, landing him among the worst tackles in the NFL.

Antonio Brown and Heath Miller had +2.7 grades in the win.

More from Behind the Steel Curtain:

• Steelers Postgame News, Updates and Analysis
• Steelers defense just may lack talent
• It's time for the Steelers to make a change at left tackle
• Antonio Brown among statistical leaders
• Johnson, Heyward score highest grades
• Four things we learned in another Steelers loss
• Lost in the loss was an impressive debut for Le'Veon Bell
• Postgame injury report: Foster left with chest injury
• Twitter reaction to 0-4 start
• Steelers vs. Vikings final score: Minnesota paced by five sacks in 34-27 win over Pittsburgh
• Winners and Losers in Steelers loss to Vikings

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