The Denver Broncos had one of the worst offenses in the NFL this year.  The team ranked in the bottom three in both passer rating and Adjusted Net Yards per Attempt, while the rushing game was just average.  The team ranked 24th in points scored per drive, yet was able to secure the No. 1 seed in the AFC.

The reason, of course, is that the Broncos had the best defense in the NFL this year, and it wasn’t particularly close. Denver’s defense lead the NFL in both net yards per pass attempt and yards per rushing attempt, joining the 2008 Steelers, 1991 Eagles and 1987 Bears as the only teams to pull off that feat since 1970. Pittsburgh won the Super Bowl in 2008, Philadelphia missed the playoffs in ’91 despite a 10-6 record and arguably the greatest defense of all time and Chicago lost to Washington in the playoffs, with a Darrell Green punt return providing the winning score.

Denver didn’t lead the NFL in points allowed, but that’s a bit misleading. Peyton Manning threw three interceptions that were returned for touchdowns, which increases the number of points allowed by the team even though the defense wasn’t on the field. And the defense had four pick-sixes of its own, along with a game-winning fumble return for a touchdown against the Chiefs. Thought of another way, the Broncos allowed 32 touchdowns this year, which means the defense allowed only 29; give the defense credit for the touchdowns it produced, and the defense allowed only 24 “net” touchdowns.

And that was despite Denver’s defense facing a whopping 201 drives, second most in the NFL to Philadelphia. That means the Broncos defense allowed a touchdown only once every 8.4 drives; the best rate in the NFL.

Rk Team Def. TD Allowed Def. TD Scored Net TD Drives Drives/TD
1 Denver Broncos 29 5 24 201 8.4
2 Seattle Seahawks 24 3 21 174 8.3
3 St. Louis Rams 28 3 25 198 7.9
4 Carolina Panthers 32 5 27 196 7.3
5 Cincinnati Bengals 26 1 25 180 7.2
6 Kansas City Chiefs 32 6 26 183 7
7 Arizona Cardinals 33 6 27 186 6.9
8 New York Jets 29 0 29 194 6.7
9 Houston Texans 34 3 31 198 6.4
10 New England Patriots 32 2 30 190 6.3
11 Minnesota Vikings 31 3 28 177 6.3
12 Green Bay Packers 33 3 30 182 6.1
13 Pittsburgh Steelers 35 2 33 189 5.7
14 Oakland Raiders 37 1 36 191 5.3
15 Dallas Cowboys 35 1 34 177 5.2
16 Buffalo Bills 40 3 37 191 5.2
17 Indianapolis Colts 43 5 38 194 5.1
18 Baltimore Ravens 40 2 38 187 4.9
19 Atlanta Falcons 39 4 35 172 4.9
20 Philadelphia Eagles 46 4 42 203 4.8
21 Washington Redskins 40 2 38 181 4.8
22 San Diego Chargers 39 1 38 180 4.7
23 Jacksonville Jaguars 44 3 41 194 4.7
24 Miami Dolphins 44 3 41 191 4.7
25 San Francisco 49ers 41 1 40 182 4.6
26 New York Giants 46 4 42 190 4.5
27 Tampa Bay Buccaneers 43 3 40 180 4.5
28 Chicago Bears 40 0 40 175 4.4
29t Tennessee Titans 45 2 43 186 4.3
29t Detroit Lions 45 2 43 186 4.3
31 Cleveland Browns 45 2 43 179 4.2
32 New Orleans Saints 57 1 56 180 3.2

Advanced systems, such as Football Outsiders, are similarly bullish on this generation of the Orange Crush: according to DVOA, the 2015 Broncos rate as the 8th best defense since 1989. Similarly, ESPN Stats and Information projects the Broncos defense as 7.0 points better than the average team; the Panthers are the second best, but at a distant plus-4.0. Finally, based on Pro-Football-Reference data, the Denver defense easily lapped the field in Expected Points Added. The Broncos have, at a minimum, one of the best regular season defenses in recent history. The question is, can the Broncos win with “only” a great defense?

Football Outsiders has published its DVOA ratings — which measures a team’s efficiency by comparing success on every single play to a league average based on situation and opponent — going back to 1989, and we can use estimated DVOA ratings to rank Super Bowl teams from prior to that season. Because DVOA measures scoring, defenses are better when they are negative, while offenses are better when they are positive.  The worst offensive DVOA rating of any team to make the Super Bowl belongs to the 2000 Ravens, at minus-8.1 percent.  After that Baltimore squad, the worst offensive teams to make the Super Bowl since 1989 are the 2006 Bears (who lost to Manning’s Colts in the Super Bowl) and the the 2003 Panthers; each team had a minus-5.0% offensive DVOA rating. Only four Super Bowl champions since 1989 have had negative offensive DVOA ratings: those Ravens, the 2002 Bucs (minus-3.8 percent), the 2008 Steelers (minus-1.5 percent), and the ’07 Giants (minus-1.1 percent).  The former three teams had three of the best defenses ever, while the latter was one of the luckiest most unusual champions of all time.

This year’s Denver offense posts a minus-8.8 percent DVOA rating, which would make it the worst offense to make the Super Bowl since 1989.  If we use estimated DVOA ratings, only the ’79 Rams (-13.1 percent) were worse.  The worst offense by any Super Bowl champion prior to 1989, using estimated DVOA, was the 1980 Raiders, at -7.7 percent.  Therefore, by either measure, the Broncos would be an incredible outlier to even make the Super Bowl, much less win it.

The 2000 Ravens’ profile looks remarkably similar to this year’s Broncos teams.  That Baltimore squad had an offensive DVOA of minus-8.1 percent, and a defensive DVOA of minus-23.8 percent; the 2015 Broncos have an offensive DVOA of minus-8.8 percent, and a defensive DVOA of minus-25.8 percent.  That makes this Broncos team look like a carbon copy of the ’00 Ravens, despite Baltimore having a journeyman Trent Dilfer at quarterback, with the Broncos having arguably the greatest quarterback of all time.

How many teams are similar to the ’00 Ravens or ’15 Broncos — i.e., great on defense, and much better on defense than offense — and wound up making it to the Super Bowl?  Using actual or estimated DVOA, only seven Super Bowl teams, 1) had a defensive DVOA of better than -15.0 percent and 2) have a defensive DVOA grade at least 25 percentage points better than its offensive grade.

Four of them won the Super Bowl: the ’02 Bucs (-31.8 percent defense, -3.8 percent offense); ’74 Steelers (-28.9 percent; -3.4 percent), ’00 Ravens (-23.8 percent; -8.1 percent); and ’08 Steelers (-29.0 percent; -1.5 percent).  You’ll note that both Pittsburgh teams — perhaps like this year’s Broncos — featured a superstar quarterback having a down season.  In 1974, future Hall of Famer Terry Bradshaw had not yet become the quarterback we would think of in later years; meanwhile, Ben Roethlisberger had one of the worst seasons of his career in the 2008 regular season, but a great Pittsburgh defense carried the team to a 12-4 record. In addition to those four teams, the ’79 Rams (-19.2 percent, -13.1 percent), ’69 Vikings (-32.9 percent, 3.8 percent), and ’06 Bears (-20.1 percent, -5.0 percent) also made it to the Super Bowl with strong defense-heavy identities.

The Broncos would be the second most extreme team to make the Super Bowl by this measure, behind only the ’02 Bucs. And they would be the worst offense to win the Super Bowl, behind only the ’00 Ravens. It wouldn’t be shocking that some team eventually would make the Super Bowl with a really bad offense; the surprising part is that it would be a Peyton Manning team. Two of Manning’s three Super Bowl teams — the ’13 Broncos, and ’06 Colts — rank as the 3rd and 10th best offensive teams of the 98 teams to make the Super Bowl. But this year, Manning would be the role player along for the ride.  After years of the shoe being on the other foot, perhaps Manning has earned that right.

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