The New England Patriots of the 21st century are the NFL's greatest dynasty. The Pats have won five Super Bowls since 2001, and next Sunday they will make their ninth appearance in the game in the past 18 seasons. (You can stream Super Bowl LIII right here on CBSSports.com.) There has never been a sustained run of success like this in modern NFL history, and there almost surely will never be one again. 

Throughout this incredible run, the Patriots have maintained a few constants. 

There's Bill Belichick, of course, the greatest coach in NFL history. Belichick is a five-time Super Bowl winner, nine-time AFC champion and three-time Coach of the Year who is the fourth-winningest coach in the history of the sport and who has the best winning percentage of anybody in the top 10. Belichick has also coached and won more playoff games than anyone in NFL history and has the second-best winning percentage of any coach who has coached at least 10 playoff games. (Vince Lombardi went 9-1 in the playoffs. There's a reason the Super Bowl trophy is named after that guy.) 

There's also Tom Brady, of course, the greatest quarterback in NFL history. Brady has been along for the ride with Belichick since he took over for Drew Bledsoe in the second game of the 2001 season. All the winning Belichick has done, he has done with Brady, with the exception of the 2008 season when Brady tore his ACL, and the first four games of the 2016 season, when Brady was suspended. Brady, like Belichick, has won more Super Bowls and more playoff games than anybody else ever has, and he has a host of regular-season and career records as well. 

The third constant for the Patriots, one that has stuck around through countless iterations, is the production they have gotten out of their offensive line. New England has started 41 different players along the offensive line since 2001, ranging from Matt Light's 153 starts to Thomas Welch's single game in the starting lineup. For all but two of those seasons, the Pats have relied on legendary offensive line coach Dante Scarnecchia to scheme things up front. With the exception of a two-season stint with the Colts in 1989-90 and a two-year "retirement" in 2015-16, Scarnecchia has been with the Patriots every single season since 1982. He started off coaching special teams and tight ends, but has been the offensive line coach since 1999. 

Thanks to the essential work of Football Outsiders, we can grab some offensive line data on the Patriots going all the way back to Brady's first season in 2001. And with the exception of that specific season, they have had an elite offensive line pretty much every single year under Scarnecchia. They've ranked inside the top 10, on average, in both Adjusted Line Yards (ALY, which assigns credit to the offensive line in the run game based on a percentage of yards gained per carry) and Adjusted Sack Rate (ASR, which adjusts sacks allowed for down, distance and opponent) for the entirety of his tenure, and in most years have been inside the top 10 in both metrics.

(Note: The offensive line coach in 2015 and '16 was Dave DeGuglielmo. We also didn't include the 2008 stats below, which were accumulated when Matt Cassel was playing quarterback for the majority of the season.)

YearOL CoachALYASR
2001Scarnecchia1026
2002Scarnecchia97
2003Scarnecchia2313
2004Scarnecchia55
2005Scarnecchia276
2006Scarnecchia128
2007Scarnecchia14
2009Scarnecchia52
2010Scarnecchia16
2011Scarnecchia28
2012Scarnecchia35
2013Scarnecchia19
2014 DeGuglielmo52
2015 DeGuglielmo218
2016Scarnecchia96
2017Scarnecchia113
2018Scarnecchia31
Belichick/BradyPatriots7.08.2

But as all football fans know, pass-blocking is about more than just preventing sacks. Pressure is often just as meaningful -- if not more so. And the Patriots have been even better at preventing pressure than they have been at preventing sacks, especially under Scarnecchia's watch. 

Pro Football Focus only has data going back to the 2006 season, but that data tells a clear story: The Patriots' offensive line has kept pressure out of Brady's face on a consistent basis, ranking inside the top 10 in lowest pressure rate in 10 of Scarnecchia's 11 seasons coaching the offensive line. In years where the league average pressure rate was 33 percent, Brady was sacked, hit or hurried on only 28.5 percent of his drop-backs -- a difference of 4.5 percentage points that works out to his being pressured about 14 percent less often than the average quarterback. During the two seasons DeGuglielmo was the offensive line coach, those figures dropped to 3.0 percentage points and 9 percent less often than average, respectively. 

YearOL CoachPressure %RankNFL AVGDiff
2006Scarnecchia29.7%733.7%-4.0%
2007Scarnecchia29.6%632.7%-3.1%
2009Scarnecchia25.6%629.7%-4.1%
2010Scarnecchia31.0%1233.0%1.3%
2011Scarnecchia26.2%631.8%-6.8%
2012Scarnecchia25.0%231.5%-6.8%
2013Scarnecchia32.6%735.5%-2.9%
2014 DeGuglielmo28.9%733.9%-5.0%
2015 DeGuglielmo34.9%1135.7%-0.8%
2016Scarnecchia30.9%1133.7%-2.8%
2017Scarnecchia31.4%834.9%-3.5%
2018Scarnecchia25.8%333.9%-8.1%
2006-13, '16-18Scarnecchia28.5%6.833.0%-4.5%
2014-15DeGuglielmo31.8%9.034.8%-3.0%

In other words, Scarnecchia is Good At This. And the 2018 season was no exception. In fact, it might have been his crowning achievement. Brady was pressured on only 25.8 percent of his drop-backs this season, per PFF, the third-lowest rate in the league. That rate was 8.1 percentage points and 23.9 percent south of the NFL average, each the single best marks of the PFF era for the Patriots. And Scarnecchia and company did this with an offensive line made almost entirely out of patchwork parts. 

The five most commonly used linemen this season for New England were left tackle Trent Brown, left guard Joe Thuney, center David Andrews, right guard Shaq Mason and right tackle Marcus Cannon. That quintet combined to start 75 of a possible 80 games along the offensive line. Here's how the Patriots acquired those players: 

  • Brown, a former seventh-round pick of the 49ers in 2015, was acquired last offseason as part of a pick swap. The Patriots sent the No. 95 overall pick in the 2018 draft to San Francisco in exchange for Brown and the No. 143 pick, which is essentially like giving up a mid-fourth round pick for a starting left tackle. 
  • Thuney was a third-round pick in 2016. He has started all 48 regular-season games for the Patriots since that point. 
  • Andrews was signed as an undrafted free agent out of Georgia in 2015. He made the team out of camp and started right away, and has started 57 of a possible 64 games since. 
  • Mason was selected with a 2015 fourth-round pick. He played as part of a rotation during the early part of his rookie season before sliding into the lineup for good, and has blossomed into one of the very best guards in the league. 
  • Cannon was a fifth-round pick in 2011 who started a grand total of 11 games in his first four years. He slid into the lineup for an injured starter in 2015 and never gave up the spot, and has started every game that he has been healthy over the past four seasons. 

That's a full offensive line built out of mid- and late-round picks. That's pretty ridiculous in and of itself. But that group was not sieve-like, which you would expect such a unit to be. Rather, it was arguably the single best line in the league this season, ranking third in Adjusted Line Yards, first in Adjusted Sack Rate and third in pressure rate. All for the ridiculously low cost of just $14,539,489 against the cap. By way of comparison, consider the Chargers, who took on a cap hit of $14,968,750 this year for just left tackle Russell Okung, who gave up more sacks during the Chargers' divisional round loss to the Patriots (one) than the Patriots have all postseason.

Listen to Brady Quinn and Will Brinson discuss the Patriots' strategy for Super Bowl LIII on the Pick Six Podcast:

During the playoffs, the Pats have been even better up front than they were during the regular season. While Brady's pressure rate of 25.8 percent during the year was already absurdly low, it has plummeted to a completely ridiculous 15.6 percent in two postseason contests. In fact, Brady has not even been sacked during New England's run to the Super Bowl. And he has been hit while throwing the ball only one time in 90 attempts. 

And while all those numbers sound pretty ridiculous, what's even more ridiculous is that this line's run-blocking might be just as good or even better than its pass-blocking. As previously mentioned, the Pats ranked third in Football Outsiders' Adjusted Line Yards. They also ranked fourth in stuff rate, allowing only 15.9 percent of runs to be stopped at or behind the line of scrimmage. That blocking helped New England to the ninth-most efficient rushing attack in the league, per DVOA, and it helped Sony Michel rank ninth in rushing success rate out of 47 players with 100 carries or more during the regular season. Michel also ranked 13th among the 60 running backs who played at least 250 snaps this season in yards before contact per attempt. James White ranked second.

Since the team's bye in Week 11, the Patriots have become an increasingly run-heavy team. They called for a run on 49 percent of snaps from Week 12 through Week 17, the third-highest rate in the NFL, according to Sharp Football Stats. They had a 53 percent success rate on those runs, making them one of the best rushing teams in football. During their two playoff games, they've been nearly as run-heavy and nearly as successful: 48 percent of their playoff plays have been runs and they've been successful on 51 percent of those plays. 

The Patriots have increasingly relied on different, heavier personnel groupings than the rest of the league, using either two tight ends, two running backs or both far more often than other teams. They've been in 11 personnel (one tight end, one running back) only 37 percent of the time during the playoffs, meaning they've had at least two tight ends or two backs -- like fullback James Develin -- on the field 63 percent of the time, even more than they did during the regular season. That's unusual in today's NFL, but the Patriots make it work for them because they just block the guys in front of them. They clear the way for Michel and White and Rex Burkhead, and they keep defenders away from Brady. And they've been doing it for a long, long time.