How important is the offensive line to an NFL team’s success?

When it comes to winning in football, many people point to the play of the quarterback, defense or the brilliant mind of a coach as the reason for a team's performance. Rarely does the offensive line receive the spotlight.

Just how important are the men in the trenches? The New England Patriots boasted one of the best offensive lines in the league the last three times they won the Super Bowl, but is a good line absolutely necessary to claim the Lombardi Trophy?

Let's take a look at the best offensive lines in the NFL through Week 5 of the 2019 season and dive into Super Bowl history to determine how much of a factor the unit is to a team’s success.

Top 5 offensive lines—run blocking

(*Based on Football Outsiders’ analysis, teams are ranked according to adjusted-line yards, a formula that takes all running back carries and gives responsibility to the offensive line based on the following—losses: 120% value, 0-4 yards: 100% value, 5-10 yards: 50% value, 11+ Yards, 0% value)

In 2018 the San Francisco 49ers ranked 10th in adjusted line yards and 13th in rushing yards per game (118.9). This season the Niners have not only shocked the NFL with a 4-0 start but shot to first in the league in rushing yardage (200 per game), behind the running back trio of Matt Breida (85 YPG), Tevin Coleman (60 YPG) and Raheem Mostert (59.0 YPG). The offensive line is ranked No. 1 in run blocking, with 5.40 adjusted line yards.

The Oakland Raiders are another team off to a better-than-expected start and now own a 3-2 record after last weekend’s win over the Chicago Bears in London. Rookie Josh Jacobs is enjoying an outstanding beginning to his career, as he’s put up the sixth-most rushing yards in the league (430) through five games.

Oakland revamped its line in the offseason, with the addition of left guard Richie Incognito and right tackle Trent Brown, who won a Super Bowl with the Patriots in 2018. The Raiders now rank third in run blocking and sit second in the AFC West.

The Denver Broncos are the lone team with a losing record in the top five and have struggled to get much production from their rushing attack. However, in their lone win of the season against the Chargers, running back Phillip Lindsay broke free for 114 yards on 15 carries.

Run blocking may not be essential to a team's success, but in general the top run-blocking lines hail from a squad with a winning record. Of the top 15 in run blocking, just three teams own a losing record (Denver, Arizona and the New York Giants).

Top 5 offensive lines—pass protection

(*Based on Football Outsiders’ analysis, teams are ranked according to adjusted sack rate, which gives sacks and intentional grounding penalties, per pass attempt, adjusted for down, distance and opponent)

Once again the 49ers rank near the top in this category, and the majority of the top five in pass protection come from teams with a winning record. The Steelers rank first in pass protection but have just one win to show for it. That is likely because Ben Roethlisberger is out for the season with injury and the Steelers have had to adjust with quarterback Mason Rudolph, who lit up the Bengals for 229 yards and two scores on 85.7% passing in Pittsburgh’s only victory.

Only four front lines in the top 15 in pass protection own a losing record (Pittsburgh, Atlanta, Jacksonville and the Giants).

Top 5 NFL teams 2019

Run blocking and pass protection are important to a team's success but not entirely indicative of it. Can a team be the best in the NFL with just a mediocre offensive line? Looking at the top five teams in the league, based on record, the undefeated 49ers flaunt the best offensive line, while the unbeaten the Patriots feature a good—not great—unit that has  been dealing with injuries.

The Chiefs and Packers do a decent job of protecting their quarterbacks, but both rank near the bottom in run blocking. Kansas City and Green Bay have lost just once this year and are among the top five candidates to win the Super Bowl, according to oddsmakers.

Bottom 5 NFL teams 2019

The best teams can get by with average offensive lines, but bad lines may be a recipe for disaster. The five teams with the worst records in the NFL all feature fronts that rank near the bottom in run blocking, and almost all of them struggle equally with pass protection.

If you're wondering why a team like the Cleveland Browns is falling apart, despite the talent on its roster, the offensive line might be the place to blame. Cleveland's line is 26th in pass protection and has allowed quarterback Baker Mayfield to get sacked 16 times (eighth most in the league) in the early season.

The Browns offensive line also relies on running back Nick Chubb to compensate for its weaknesses. According to Football Outsiders, a team with a low ranking in adjusted-line yards and a high ranking in open-field yards is heavily dependent on its running back to break free for long runs to make the running game work. Cleveland's offensive line is listed at fourth in open-field yards, compared to 20th in run blocking.

O-lines of last 5 Super Bowl winners

The New England Patriots have consistently won Super Bowls behind solid offensive lines, but note that the Pats' scoring defense had a lot to do with their dominance in each of their last three championship seasons, as well.

If you examine the other two teams that won Super Bowls in the last five years, neither had a stellar offensive line. The Eagles ranked 22nd in run blocking and 12th in pass protection in 2017's Super Bowl-winning campaign, and the Broncos' front line was about as good in 2015, when Peyton Manning led Denver to victory in Super Bowl 50.

Scoring defense seemed to be the key, as the Eagles and Broncos ranked fourth in points allowed per game.

How important is the offensive line?

The moral of the story? The offensive line can be just OK if other pieces on the team can make up for it. But if the offensive line is a disaster, there's a good chance the rest of the offense, and the team's record, are suffering as a result.