Previous Articles In Series:
Ground Rules:
- No player comparisons: Generalities about players are irrelevant because they are just opinion. Number of Pro Bowlers or Hall of Famers often reflects popular opinion more that actual talent. Should someone want to quantify the quality of each player at each position and aggregate the total talent, I would love to read it. Until then, we will look at the whole team performance.
- Relative > Absolute: A team that holds opponents to 11.4 points per game (ppg) sounds better than a team that holds opponents to 14.2 ppg. But when the average offense scored 15 ppg in the year of the first team and the average offense scored 27 ppg in the year of the second team, the judgment should shift. We will heavily slant toward how the team performed in the era/year in which they played. This will also help to account for rule changes.
- Quality of opponent matters: A team that has the best opponent scoring average in the league, and does it during a year when scoring is way up sounds dominant. But what if they played in the 2005 NFC West? Who you play, and how you perform against those opponents needs to be taken into account.
- Strength of offense: A defense that has to make up for a horrible offense gets extra credit. We will compare the offenses these defenses played with at a high level.
- Championships: It should not be the ultimate arbiter, but it does have to be factored in. A defense that ends the year as a champion deserves credit for the ultimate accomplishment, and one that fails in that game deserves additional scrutiny.
- Analysis versus facts: I will give my opinion at the end of each article about which defense was superior and why. You may come to a different conclusion. The facts should not be disputable. My interpretation of them is open to debate.
Why the 2015 Broncos
Round 1: Yards Allowed
Team | League Avg Yards/Game | Opponent Yards/Game | Std Dev | League Rank |
2015 Broncos | 352.7 | 283.1 | -2.25 | 1 |
2013 Seahawks | 348.5 | 273.6 | -2.40 | 1 |
The Seahawks allowed nearly 10 fewer yards per game than the Broncos, and both teams finished atop the rankings, but the Seahawks take the lead in this category due to a better performance relative to what other league defenses were doing that year. Keep in mind, standard deviation looks at the spread of results across the league. It was 31.2 in 2013 for yards per game and 30.9 this year. That means that despite a greater spread of results in 2013, the Seahawks defense still stood out more than Denver’s in this category.
Team | League Avg Yards/Play | Opponent Yards/Play | Std Dev |
2015 Broncos | 5.5 | 4.4 | -2.65 |
2013 Seahawks | 5.34 | 4.4 | -2.22 |
Some teams give up more yards per game simply because their offense leaves them on the field a lot. Looking at yards per play allows us to see an even better apples-to-apples look at two defenses. The Broncos have a dominant advantage in this category despite giving up the same yards per play as the 2013 Seahawks. This would indicate the Broncos are probably the more efficient defense in terms of surrendering yardage. This one is close but…
ROUND ONE WINNER: 2015 Broncos
Round 2: Points Allowed
Team | League Avg Points/Game | Opponent Points/Game | Std Dev | League Rank |
2015 Broncos | 22.8 | 18.5 | -1.25 | 4 |
2013 Seahawks | 23.4 | 14.4 | -2.23 | 1 |
Team | League Avg Points/Play | Opponent Points/Play | Std Dev |
2015 Broncos | 0.354 | 0.287 | -1.29 |
2013 Seahawks | 0.360 | 0.233 | -2.07 |
It gets a tiny bit closer when looking at efficiency per play, but not much. This one is clearcut.
ROUND TWO WINNER: 2013 Seahawks
Round 3: Schedule
Up to this point, we have been comparing the two defenses performance against league averages. But neither the Seahawks nor the Broncos played every opposing offense in the league. We need to get specific about which offenses they played, and how they did relative to the averages of those offenses.
Team | Aggregate Opponents PPG | Opponent PPG | Std Dev |
2015 Broncos | 21.5 | 18.5 | -1.0 |
2013 Seahawks | 22.1 | 14.4 | -2.5 |
The Broncos 16 regular season opponents scored an average of 21.5 points per game, just below the league average (22.9). Seattle faced opponents who averaged slightly below the league average (23.4) as well. The Seahawks held their opponents much farther below their season averages than the Broncos.
Let’s step away from the regular season for a moment though and just see how both teams did against the best offenses in the league that year. The best versus the best.
Team | GMs VS TOP 10 OFF (incl playoffs) | +/- Opp Avg |
2015 Broncos | 7* | -3.7 |
2013 Seahawks | 3 | -19.9 |
Denver faced a bunch of top offenses. They did not do wonderfully against them. Their points allowed per game rose from their average of 18.5 to 23.1. The Seahawks dropped their average from 14.4 to 10.0 against the best offenses, including their dominant Super Bowl performance against the best offense in history. Denver will face one more Top 10 offense in the Super Bowl, which will impact these results, but not by much.It is also worth noting that one of the Top 10 offenses the Broncos faces was the Bengals without Andy Dalton, so it would be hard to consider that team near its best. They also faced the Steelers with an injured Ben Roethlisberger, and without Antonio Brown, Le’Veon Bell, or DeAngelo Williams.The Broncos faced more top-flight offenses, but their performance against them was underwhelming, whereas the Seahawks stepped up their game against the best.
ROUND THREE WINNER: 2013 Seahawks
Round 4: Takeaways
Team | League Avg Takeaways/Game | Takeaways/Game | Std Dev | League Rank |
2015 Broncos | 1.5 | 1.7 | 0.6 | 8 |
2013 Seahawks | 1.6 | 2.4 | 2.3 | 1 |
The numbers flip here. The higher, the better. Seattle was significantly more adept at taking the ball away from their opponents than the Broncos. Denver was pretty close to a league average defense when it comes to creating turnovers. This round is not close.
ROUND FOUR WINNER: 2013 Seahawks
Round 5: Offenses
Let’s take a look at just how much help or harm the other side of the ball did to these defenses. Admittedly, I will not go is deep here or else this would turn into an equally long assessment of each offense. Instead, we will stick to some absolute numbers and get some relative information via league rankings.
Team | OFF PPG | OFF PPG Rank | OFF YDS/GM | OFF YDS/GM Rank | TO/GM | TO/GM Rank |
2015 Broncos | 22.2 | 19 | 355.5 | 16 | 1.94 | 29 |
2013 Seahawks | 26.1 | 8 | 339 | 17 | 1.19 | 4 |
This one is interesting. The Broncos offense was clearly worse in terms of scoring, but was similar in yards. The stat that jumps out here is the turnovers. The Broncos offense turned the ball over at an alarming rate, ranking 29th in the NFL. This put considerably more strain on their defense than what the 2013 Seahawks offense did. This helps to explain at least some of the difference in points allowed.
ROUND FIVE WINNER: 2015 Broncos
Overall Winner: 2013 Seattle Seahawks
This is the only subjective part of the article. I look at these two defenses and see some similarities, but the Broncos biggest advantages were in yards per play and the fact that their offense put them in bad situations due to turnovers. Seattle dominated in points allowed, points per play, yards allowed, and turnovers forced, and by a pretty large margin in most.The 2015 Broncos are a great defense. They can help their legacy by finding some way to win this Super Bowl, but they will have to wait in line behind the 2013 Seahawks when awards are being given out for best defenses of all-time.