Many personnel people will tell you that these days, the most important positions on an NFL team break down like this: quarterback, edge rusher, shutdown cornerback. But teams are built in all kinds of ways. Two years ago, the San Francisco 49ers won the NFC with a decent quarterback, an average secondary, outstanding edge pressure, and the NFL's best offensive line. The Patriots' recent streak of domination in the AFC East has its roots in a succession of underrated offensive lines, and we all remember how important the line was to the Jimmy Johnson-era Dallas Cowboys. The Cowboys fell into disarray over the next two decades after winning three Super Bowls in four years in the early- and mid-1990s, and the franchise didn't return to full force until a re-commitment was made to the front five.
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Depending on the construction of a team, the offensive line can be of paramount importance, and it's certainly a major concern no matter what a team's strengths are. With that in mind, it's time for a ranking of the offensive lines of the eight teams left in the 2014-2015 postseason.
These overall line rankings were compiled off of general tape study through the season and four different performance metrics: Football Outsiders' Adjusted Line Yards and Adjusted Sack Rate stats, and Pro Football Focus' Total Pressures Allowed and Pass Blocking Efficiency. FO's ALY and ASR metrics are adjusted for down, distance and opponent -- Adjusted Line Yards attempt to determine how much a line is responsible for a team's rushing attack, and Adjusted Sack Rate tracks sacks (plus intentional grounding penalties) per pass attempt adjusted for down, distance, and opponent.
PFF's metrics are based on their charting -- Total Pressures Allowed include sacks, quarterback hits and quarterback hurries, and Pass Blocking Efficiency is a weighted formula that combines sacks, hits and hurries relative to how many passing snaps each team has. PFF's stats aren't opponent-adjusted, but their sack metrics do tend to separate line performance in pass protection more specifically. Of course, numbers aren't the be-all, end-all, which is where the tape study comes in, but here's a fairly comprehensive breakdown of the best and worst offensive lines for the eight remaining playoff teams.
1. Dallas Cowboys (First in Adjusted Line Yards, 17th in Adjusted Sack Rate, fifth in Total Pressures Allowed, tied for fourth in Pass Blocking Efficiency)
There's no question that the Cowboys have the best run-blocking line in the NFL -- they helped convert 76 percent of all short-yardage runs on third or fourth down and in the red zone, the team's second-level blocking has been stellar, and Tyron Smith might be the league's best left tackle. Dallas has some issues in pass protection, but when you have a team with a Sack Rate in the middle of the pack and a Total Pressures Allowed in the top five, you've probably got a quarterback who's working his way into some sacks -- and that's always been true of Tony Romo. PFF, in fact, has Romo responsible for six of his sacks this season, while left guard Ronald Leary and right tackle Doug Free are responsible for three each. Leary and Free are the weak links overall, but in Smith, center Travis Frederick and right guard Zack Martin, the Cowboys have hit big on a great foundation.
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2. Baltimore Ravens (Third in Adjusted Line Yards, fourth in Adjusted Sack Rate, sixth in Total Pressures Allowed, tied for fourth in Pass Blocking Efficiency)
Were it not for undrafted rookie left tackle James Hurst starting through Baltimore's postseason (the first undrafted rookie ever to start at that position in the playoffs), we might give the Ravens a better shot at the top slot here. As much as Dallas' line is given credit for the team's success this season, the Ravens' line should be given more praise for Baltimore's offensive turnaround, especially in the run game. That has a lot to do with first-year offensive coordinator Gary Kubiak. Switching to a power zone system was of great benefit to everyone on the line, and Baltimore's Line Yards shot up from a league-worst 3.01 per carry in 2013 to 4.23 per carry in 2014. In pass protection, guards Marshal Yanda and Kelechi Osemele have been the stars -- overall, it's hard to name a better guard tandem.
3. Denver Broncos (12th in Adjusted Line Yards, first in Adjusted Sack Rate, first in Total Pressures Allowed, first in Pass Blocking Efficiency)
Yes, any line protecting Peyton Manning will get the benefit of Manning's quick release and defensive understanding, but the team's successful switch to a power-running attack in the second half of the 2014 season as Manning's arm strength declined is pretty rare. Moving Orlando Franklin from tackle to guard has been a big part of that, as has the outstanding season put in by the underrated Louis Vasquez, who logged equal time at right guard and right tackle this season and has given up just four sacks and 26 total pressures. Left tackle Ryan Clady is the star, but there's a lot of talent here.
4. Green Bay Packers (Eighth in Adjusted Line Yards, 13th in Adjusted Sack Rate, second in Total Pressures Allowed, second in Pass Blocking Efficiency)
Left guard Josh Sitton has been the star of Green Bay's line for a long time -- Ndamukong Suh once told me that Sitton gives him more trouble than any other blocker. Sitton allowed no sacks and just 10 total pressures in 1,016 offensive snaps this season, helping the Pack's offense move in a more power-based direction with running back Eddie Lacy at the helm. One guy who is getting hot at the right time is left tackle David Bakhtiari, who has allowed just one sack overall since he gave up two to the Saints in Week 8.
5. New England Patriots (Fifth in Adjusted Line Yards, second in Adjusted Sack Rate, 21st in Total Pressures Allowed, 19th in Pass Blocking Efficiency)
Pass protection might be the Patriots' Achilles' heel, which comes down to the linemen for the most part, although there are times when Tom Brady takes more time than he has to find open receivers these days. Interior linemen Dan Connolly and Ryan Wendell are the primary culprits in terms of allowing pressure, and that's a problem, because Brady does much better when he's pressured from either side than when he's getting defenders right in his face.
6. Seattle Seahawks (Fourth in Adjusted Line Yards, 24th in Adjusted Sack Rate, 12th in Total Pressures Allowed, 23rd in Pass Blocking Efficiency)
It could be said that the Seahawks won the Super Bowl last season in spite of their offensive line, not because of it, and that's been just as true this season. It's a line that relies tremendously on Marshawn Lynch's ability to break tackles and create openings, along with Russell Wilson's knack for escaping pressure and making big plays. That said, Wilson is also responsible for a lot of his own takedowns, as any mobile quarterback will be. The two stars on this line are left tackle Russell Okung and center Max Unger, and both players have missed time this season due to injury. Overall, it's a decent run-blocking line with some unique challenges given Seattle's schematic constraints, but in a general sense, this line hurts more than it helps. Rookie right tackle Justin Britt has allowed 49 total pressures this season, second-most among any lineman on the remaining playoff teams.
7. Indianapolis Colts (15th in Adjusted Line Yards, seventh in Adjusted Sack Rate, 32nd in Total Pressures Allowed, 20th in Pass Blocking Efficiency)
If people want to debate how great Andrew Luck is, how many NFL quarterbacks would keep leading their teams to the playoffs despite the lack of any kind of run game and an offensive line that gives up tons of pressure? It should be noted that Indy's Total Pressures Allowed ranking is a bit skewed because the Colts have such a high-volume passing attack, but the PBE numbers don't go up much when you take that into consideration. Right tackle Gosder Cherilus is the main offender here, with six sacks and 48 total pressures allowed. That said, right tackle Anthony Castonzo, who has taken time to develop, has allowed just two sacks in 1,267 snaps this season. That's impressive.
8. Carolina Panthers (27th in Adjusted Line Yards, 22nd in Adjusted Sack Rate, 25th in Total Pressures, 24th in Pass Blocking Efficiency)
Outside of Vikings left tackle Matt Kalil, who should probably have his own "turnstile" category, no offensive lineman has allowed more sacks in the 2014 season than Panthers left tackle Byron Bell, who gave up nine takedowns, five quarterback hits and 38 hurries. Right tackle Nate Chandler gave up seven sacks and 31 total pressures in just 703 total snaps. Left guard Amini Silatolu allowed six sacks in just 413 snaps before he was felled by a knee injury in Week 10. Yes, Cam Newton is a mobile quarterback, but those numbers are not good at all. The recent resurgence of the Panthers' run game is attributable in part to guards Andrew Norwell and Trai Turner. Neither has allowed a sack this season, and both have been strong run-blockers.