PFF ranks the Cardinals’ O-line last in the NFL

It’s easy to spot why the Arizona Cardinals have produced one of the most underwhelming offensive attacks in the NFL through 10 weeks.

Quarterback changes or not and offensive coordinator swaps or not, the offensive line hasn’t produced in either the passing game or the running game.

True, it didn’t help that a dead-armed quarterback Sam Bradford limited the dynamics of the offense and rookie Josh Rosen has worked through the expected hurdles since. But the work up front by four first-round picks and a rookie center has been hardly average at its best moments. That’s if those players have been healthy.

The latest hit to the line came Sunday against the Kansas City Chiefs when right guard Justin Pugh injured his MCL, putting him on the injured reserve for the year. That happened after left guard Mike Iupati was a pregame scratch with a back issue.

What happened from there wasn’t a one-game blip. The unit has struggled all year, and Pro Football Focus graded the Cardinals line as the worst in the NFL through Week 10.

They’re going to have a tough time digging themselves out of last place this season, especially if they have to resort to backups. Jeremy Vujnovich allowed three sacks filling in at left guard against the Chiefs while both Cardinals tackles allowed six pressures.

Is there any room for improvement?

Individually, left tackle D.J. Humphries has graded out by PFF as the best player on the line. He’s the 11th-rated tackle in run blocking but just 59th in pass protection for a 31st overall grade.

Right tackle Andre Smith has been rated decently in the run (15th among tackles) but poor in the pass (63rd). The guards have struggled in most respects, and now it’s a wonder if replacements that could include veterans Vujnovich and Oday Aboushi — plus the depth of three rookies without experience — can take on larger roles with success.

The odd news coming from an injury-battered line is that the Arizona offense on Sunday actually looked relatively improved from its past games. At the least, it was helped out by offensive coordinator Byron Leftwich in his second game with play-calling responsibilities.

Johnson took 21 carries for 98 yards, a 4.7 average that was more than a yard per carry better than what he’d posted coming into the Chiefs game.

Rosen completed 22 of 39 passes for 208 yards, a touchdown and two interceptions. The pass protection wasn’t as effective, as he took five sacks and was hit 13 times.

Protecting Rosen’s health for the long-term was something Leftwich spoke on in his first meeting with the media since taking over for fired OC Mike McCoy.

He’ll have to include that priority in his game plan for beating the Oakland Raiders at State Farm Stadium on Sunday.

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