Pro Football Focus has been ranking each positional group, and they’re onto the defensive line. PFF says, “the best defensive lines have both high-end players and depth, and that’s what we leaned on when putting together this ranking.”
For most defensive rankings, you won’t have to go far to find the San Francisco 49ers. I thought for sure they’d be the top unit here. If not, maybe the Steelers. Pittsburgh was No. 1, but the Niners weren’t second or third on PFF’s list. Instead, they were fourth, after Washington’s football team:
Nick Bosa enters Year 2 of his NFL career after setting the rookie record for most total pressures in a season (80). He broke a record that had stood since 2011 — by 16 pressures, no less — and that doesn’t even count the fact that he still had his foot on the gas by the time the Super Bowl rolled around. The 49ers traded away DeForest Buckner, who had been the team’s most consistent interior force over the past few seasons, but they used the pick they acquired on his direct replacement — South Carolina’s Javon Kinlaw.
Kinlaw was the most effective pass-rushing interior lineman in this draft, slotting in as the No. 1 player at his position on PFF’s Big Board because of it. Hitting the ground running as a rookie is tough, but Kinlaw has the talent to immediately contribute inside. Arik Armstead and Dee Ford give the 49ers depth and talent on the edge, and Armstead can kick inside and move around the line. Armstead posted an overall PFF grade just below 90.0 last season after a career year where he racked up 62 total pressures. Meanwhile, injuries limited Ford, but when he was on the field, he backed up his breakout 2018 season.
Buckner’s departure potentially opens the opportunity of one last salvage mission for Solomon Thomas, who might finally get some playing time inside, while Ronald Blair III should still earn some rotational snaps after solid showings in past years.
I agree that “hitting the ground running as a rookie is tough,” and we shouldn’t have sky-high expectations for Javon Kinlaw just because Nick Bosa was so dominant as a rookie. That’s not fair to Kinlaw, who has big shoes to fill.
Let’s compare stats that don’t have any biases. Football Outsiders adjusted line yards statistic takes into account how many yards the line was responsible for. San Francisco was 13th, Pittsburgh was 11th, while Washington was 29th. Unless Chase Young is worth two Bosa’s, their defensive line isn’t going to make that drastic difference. “Power success,” tells you the percentage of runs on third or fourth down, with two yards or less to go, that achieved a first down or touchdown. This stat hints at which defensive lines are making the most plays when it counts in short-yardage situations. The 49ers’ power success was 50%, which was second in the NFL. The Steelers were 31st, while Washington was 16th.
All three teams were in the top five in “adjusted sack rate,” but that can be more telling for the quarterbacks each team played. Pro Football Reference keeps track of quarterback knockdowns, hurry percentage, and pressure rate. These percentages could be skewed as some teams blitz more than others. The 49ers blitzed 20.9% of the time, while Washington blitzed 23.9% of the time, and the Steelers sent an extra rusher upwards to 36.9% of the time. With that in mind, the 49ers still had the best hurry percentage. They were at 14.7%, with Washington at 13.6% and the Steelers at 11.8%. San Francisco did have a significantly worse QB knockdown percentage than Pittsburgh and Washington. These were the three best teams at pressure percentage.
Objectively, San Francisco was better last season, and unless Buckner proves to be a bigger loss than the team calculated, the 49ers will once again have the best defensive line in the NFL.