Recently I spent a fanpost looking at how bad our D was last year, but I focused solely on points allowed. Doing some further research at FO, I realized that there were some positives - if you looked hard enough for them. For those of you who are unfamiliar with FO, they are a group of folks how try to use statistics to analyze football in better ways than what is normally done. They are not perfect, and they willingly admit that, but they are better. For example their ability to evaluate the performance of a defensive front 7 is light years ahead of the standard YPC, sacks, hurries numbers which normally get discussed. After the jump we'll see what the FO analysis has to say about our 2010 front 7 and what they could and couldn't do last year.
The link talks about the DL, but if you read the disclaimer at the beginning of the page, FO freely admits that this is more an analysis of the whole front 7 than just the DL. The majority of the data is adjusted based on opponents:
Teams are ranked according to Adjusted Line Yards. Based on regression analysis, the Adjusted Line Yards formula takes all running back carries and assigns responsibility to the offensive line based on the following percentages: Losses: 120% value 0-4 Yards: 100% value 5-10 Yards: 50% value 11+ Yards: 0% value These numbers are then adjusted based on down, distance, situation, opponent, and the difference in rushing average between shotgun compared to standard formations. Finally, we normalize the numbers so that the league average for Adjusted Line Yards per carry is the same as the league average for RB yards per carry. Defensive line stats (more accurately, defensive front seven stats) represent the performance of offensive lines against each defense, adjusted for the quality of offensive opponents.
2010 Broncos Rankings relative to the rest of the league
29th in ALY at 4.40
9th in Power Success against at 57%
27th in Stuffed% at 15%
16th in 2nd level yards 1.11
26th in Open Field Rank 0.99
32nd in Adjusted Sack Rate at 4.6%
For comparison sake here are the rankings of our front 7 from 2009
17th in ALY at 4.13
20th in Power Success against at 67%
23th in Stuffed% at 17%
27th in 2nd level yards at 1.26
24th in Open Field Rank at 1.00
7th in Adjusted Sack Rate at 7.4%
So what does each of these stats tell us (I'll assume you care since you have read this far)?
ALY is essentially how our front 7 did against the run on the whole.
Power Success: Percentage of runs on third or fourth down, two yards or less to go, that achieved a first down or touchdown. Also includes runs on first-and-goal or second-and-goal from the two-yard line or closer. This is the only statistic on this page that includes quarterbacks. Teams are ranked from lowest power success percentage allowed (#1) to highest power success percentage allowed (#32).
Stuffed % is % of plays where our D tackled the RB behind the line
2nd level Yards are essentially runs that went for 5-10 yards (RB yards gained in the 5-10 yard range minus 5 yards/total RB yards gained). This tried to measure how well our LBs tackled once the RBs got to them.
Open field yards are essentially runs that went for 10+ (RB yards gained in the 10+ yard range minus 10 yards/total RB yards gained). This tries to quantify how much of the rushing yardage given up was a result of our front 7 completely missing AND our secondary also getting there late. Teams with really bad numbers here gave up a really high proportion of the total rushing yards against on really big plays.
Adjusted Sack Rate is sacks/pass attempt
So in general in 2009 and 2010 the Broncos front 7 was really bad against the run (Duh!). My 3 yr old could have told you that. :-)
In 2009 we were in the bottom half of the league in everything except sack rate. In 2010 our front 7 was actually in the top 3rd of the league in power success allowed. This was pleasantly surprising, but the smile wore off quickly when I realized that given our utter lack of a pass rush - why risk running on 3rd and short against us? So I'm concluding that our "success" in that department was merely a function of teams going with what they knew would work (throwing on third and short) as opposed to running which probably had a LOWER probability of success. Sad, I know.
Looking at 2nd level yards we actually improved in 2010 relative to 2009, meaning that we gave up a lot more 5 and 6 yards runs that 7-10 yard runs. Again, all this tells us is that our LBs were better at stopping the RBs once they got to the second level than in 2009. Our front 7 still gave up an alarming absolute number of 5-10 yard runs which is reflected in the ALY ranking for both years.
The open field number was pleasantly surprising and I couldn't find a way to make it look worse. Denver was at 0.99. The league average here was 0.70. The best team in the league (PIT) had a 0.17 value. I came into the analysis remembering that Denver gave up an absurd number of really long plays last year. What this value tells us is that the majority of those plays were in the passing game and not the running game - I have not verified this fact. The caveat here is that the average league value of 0.70 was skewed high due to JAC being the worst team in the league (1.43) by a huge margin - OAK was 31st at 1.17.
The final analysis is that front 7 was well below average in 2009 and 2010. The key difference being that in 2009 we could actually pressure the QB and take some pressure off of our secondary. In 2010 our lack of QB pressure made mediocre QBs look like Peyton Manning.
As a realists, I don't think that we are going to revive the Orange Crush D in one draft, but I do think that if we can find 4 starters in this draft with at least two of those being well above average at their position (and one exceptional) our front 7 can go from one of the worst in the league to mediocre. Keep this in mind, the 2005 Broncos D which allowed only 258 points (16.1 ppg) only had a mediocre front 7. Here is how it compared from FO
17th in ALY at 4.02
24th in Power Success at 70%
17th in Stuffed % at 19%
8th in Open Field Rank (which was called 10+% at that point)
31st in Adjusted Sack Rate at 5.0%
This proves that you can makes it all the way to the AFC championship game (and lose) with a mediocre front 7. Not that I am predicting a playoff run next year - far from it - but I am hoping for and expecting our D to improve to mediocrity (Yippee!) if we have a combination of good luck and good planning in this year's draft. Getting a healthy Doom back is like adding a high priced FA who will, if nothing else, give us a better pass rush next year. If we add two above average DTs and Ayers stays healthy, we should have a much improved front 4 next year. Whether or not we upgrade our LB core will depend on the aforementioned luck and planning in the draft. We could very easily end up drafting some more under-achieving and/or injury prone LBs like we currently have on our roster.
Happy Draftivus and let's put the "D" back in Denver!