In this week's Varsity Numbers, Bill Connelly revisits some measures and concepts: Adjusted Scores, Covariance, and momentum (or whatever you choose to call it).
21 Jan 2005
by Aaron Schatz, with additional analysis by Michael David Smith
For a team that went 13-1 to open the season, the Philadelphia Eagles have had to face an awful lot of probing questions in recent weeks. Last week's big question was whether they could put points on the board despite the injury to star receiver Terrell Owens. This week, the football world is wondering whether the Eagles can overcome the legacy of three straight losses in the NFC Championship Game.
The answer to the second question should be the same as the first: a resounding "yes." None of the past Philadelphia teams dominated their conference like this year's Eagles. Philadelphia was the only NFC team to rank in the NFL's top ten according to our DVOA ratings.
The Falcons, meanwhile, rode an easy schedule (according to our rankings, the fourth-easiest in the league) sprinkled with a few spectacular wins to an 11-5 record. Predictions for this game are clouded not only by Atlanta's remarkable inconsistency but also by a weather forecast that includes high winds, temperatures in the 20s, and up to two feet of snow.
* * * * *
For those who may be visiting this site for the first time to read this preview, some explanations for our statistics. DVOA (Defense-adjusted Value Over Average) breaks down each play of the season and compares it to the NFL average based on situation and opponent. You'll find it explained further here. Since DVOA measures ability to score, a negative VOA indicates a better defense and worse offense, and a positive DVOA indicates a better offense and worse defense.
Each team is listed with DVOA for offense and defense, split into rush and pass, along with rank among the 32 teams in parentheses. (If the DVOA values are difficult to understand, it is easy to just look at the ranks.) I've also listed each team's red zone performance on offense and defense.
TREND is the WEIGHTED DVOA trend, based on a formula which drops the value of games early in the season to get a better idea of how teams are playing now (explained here). Weighted DVOA now includes playoff performance, and the weights for all teams were moved an additional two weeks ahead from the regular season. Except for TREND numbers, all DVOA statistics on this page are regular-season only unless otherwise noted.
SPECIAL TEAMS numbers are different; they represent value in points of extra field position gained compared to NFL average. Field goal rating represents points scored compared to average kicker at same distances. All special teams numbers are adjusted by weather and altitude; the total is then translated into DVOA so it can be compared to offense and defense.
Each team also gets a chart showing their performance this year, game-by-game, according to total DVOA. In addition to a line showing each game, another line shows the team's trend for the season, using a third-power polynomial trendline. That's fancy talk for "the curve shifts direction once or twice." Note that even though the chart appears in the section for when each team has the ball, it represents total performance, not just offense.
|ATL OFF||PHI DEF|
|DVOA||-6.2% (24)||-3.5% (13)|
|TREND*||0.2% (17)||-14.0% (4)|
|PASS||-34.9% (30)||-7.2% (10)|
|RUSH||16.6% (3)||0.7% (20)|
|RED ZONE||-3.7% (18)||-8.2% (14)|
It is not hyperbole to say that Michael Vick may be the finest running quarterback of all time. His value as a runner was three times greater than that of any other quarterback this season. (Scroll down on this page for QB rushing value.) Some people have said that Vick needs the artificial turf and dome in Atlanta to run wild, but you may remember that he played on grass in college and looked plenty fast back then. His one deficiency as a runner is that he needs to do a better job of holding onto the ball. His fumble against the Rams could have been costly, and it happened because he kept the ball in his left hand instead of tucking it away in his right as he ran toward the right sideline.
You may have heard that the Falcons have running backs as well. Warrick Dunn and T.J. Duckett, often ignored in Vick's shadow, are finally getting their due thanks to Atlanta's playoff run. Last year, Football Outsiders rated Atlanta as the fifth-best rushing offense in the NFL even though Vick started only four games. This year, the Falcons rated third, trailing only the Jets and Chiefs. The improvement has come not only from the return of Vick but from the arrival of former Denver offensive line coach Alex Gibbs. The Falcons' line now uses many of the cut blocks that Denver opponents hate but that league rules say are legal. Atlanta runs were stuffed at the line less often than those of any other NFL team.
The Eagles, however, substantially improved their run defense in Week 10 by re-installing Jeremiah Trotter in the middle linebacker position (check out that defensive trend DVOA). Take out the final two regular season games where most starters rested, and the Eagles have allowed only 3.7 yards per carry since Trotter rejoined the starting lineup (-16.6% DVOA). Before that, they allowed 4.9 yards per carry (7.1% DVOA). At 262 pounds, Trotter would seem to fit the bill of the linebacker who stuffs runs to the middle, but he's surprisingly nimble when pursuing runners on the outside as well. (There is speculation that Trotter will be assigned the job of shadowing Vick, much as Tampa Bay does with Derrick Brooks, and you have to wonder if this might cause the Eagles to suffer against Dunn and Duckett up the middle.)
Stopping runs to the right side is still a weakness because defensive end Javon Kearse is a pass rush specialist. But that should be less of a problem against Atlanta, because the left-handed Vick scrambled left end 49 times and right end only 20 times. Safety Brian Dawkins is also an extremely talented run-stopper, and he'll be able to help contain the Atlanta backs if he's not needed to stop the pass. And there's no reason to believe he will be. The Falcons running game is one of the best in the league, but their passing game is horrific.
Difficulties when adapting to a new offensive system are understandable, but Vick's regression as a passer since a fine 2002 season is simply bewildering. According to our ratings, the Atlanta running game -- as great as it is -- can only make half the difference between the abysmal Atlanta passing game and a league-average offense.
Vick's superficial numbers look bad, but his actual performance was even worse because he had such hard time passing in the most important situations. When he had to pass on third down, Vick converted 20% less often than a league average quarterback. The more yardage needed for a new set of downs, the worse Vick was compared to the league average.
Many would respond that Vick doesn't need to pass well on third downs because he can run. But while we all have an image in our minds of Vick scrambling for a first down against impossible odds, in reality he scrambled for a first down only twice on third-and-seven or more.
And in the red zone, Vick was completely unreliable, with as many sacks and interceptions (four and two) as touchdowns (six) when passing on goal-to-go downs. His DVOA in these situations: -107.8%. Yikes.
Because his mobility makes him think he can always rely on running away instead of throwing the ball away, Vick gets sacked more than three times a game, and now he must face the challenge of Philadelphia's complicated blitz packages. No defensive coordinator working today employs the blitz more than the Eagles' Jim Johnson, and he employs it in a variety of different formations. Jevon Kearse is known primarily as an outside rusher, and he will primarily be matched up against the inconsistent right tackle Todd Weiner (he fell down and didn't touch Leonard Little when Little sacked Vick in the Rams game). But he actually stunts to the inside at times, or lines up as a blitzing inside linebacker. Johnson will bring Dawkins on the blitz as well. Last week, Philadelphia only sacked Daunte Culpepper twice, but their pressure was constant and Culpepper was disrupted throughout the day.
When Vick does try to pass, he has only one reliable receiver: tight end Alge Crumpler. But thanks to strong linebackers as well as coverage by Dawkins, the Eagles are one of the league's best teams defending passes to tight ends (-36.5% DVOA, fourth in the NFL). Even last week they covered Minnesota's Jermaine Wiggins well enough that Daunte Culpepper only threw to him twice. That doesn't mean that Vick won't find Crumpler, but it will be harder than usual.
Once upon a time in Tampa Bay, Dunn was known as equal parts receiver and runner, but that's no longer the case. Dunn was thrown 39 passes this season -- by comparison, Philadelphia's Brian Westbrook was thrown 87 passes -- and was mostly used as a safety valve. But that safety valve might not be so safe against the Eagles, one of the league's best teams defending passes to running backs (-33.1% DVOA, fifth in the NFL). Over the course of the year, running backs failed to gain yardage against the Eagles on one out of every ten complete passes.
The Eagles' corners can be beaten deep, as Marcus Robinson showed last week when he beat Lito Shepard for a 40-yard gain. Philly's defense was actually one of the league's worst in defending number one receivers. But against Atlanta, in snowy, windy conditions, does it really matter? Peerless Price is an affront to (insert name of deity here). He ranked 78th in DVOA out of 84 wide receivers with at least 50 passes and caught only 5 of 21 third down passes intended for him this season. And two of those were thrown by Matt Schaub.
|PHI OFF||ATL DEF|
|DVOA||17.7% (6)||0.6% (16)|
|TREND*||6.7% (12)||2.3% (19)|
|PASS||21.8% (9)||1.6% (19)|
|RUSH||11.4% (6)||-0.5% (17)|
|RED ZONE||31.1% (3)||-7.9% (15)|
While Minnesota is nobody's idea of a strong defensive test, the Eagles did show last week that they could score plenty of points without Terrell Owens. After struggling for two games against Dallas and Washington, and then not even trying for two games against St. Louis and Cincinnati, the Eagles finally got their offensive act together.
As I mentioned last week, if you take out the final two regular season games where they sat their starters, Philadelphia's offensive DVOA would move from sixth to fourth, just ahead of the Patriots. (Their defense would stay pretty much the same.) To be honest, we all probably overreacted to the loss of Owens. Last year without Owens the Eagles finished with the same rank in offensive DVOA as this season, sixth. And as a couple readers have pointed out, the Eagles offense in 2003 improved markedly after a terrible start. Last year in Weeks 1-7, Philadelphia's offensive DVOA was -20.4%, 28th in the NFL. But for Weeks 8-17 of the 2003 season, Philadelphia's offensive DVOA was 37.5%, the best in the NFL. The difference between the two seasons is that last year the Eagles had Duce Staley, and thus a better running game, and this year with Owens they had a better passing attack.
Against the Vikings, the task of replacing Owens seemed to be split between 2012 WWE Royal Rumble Champion Freddie Mitchell, lining up on the outside as the number one receiver, and Brian Westbrook, who shifted over from running back to slot receiver for much of the game. Westbrook has better hands than any of the Eagles' other receivers, and this is exactly the way he was used in college at Villanova: in 1998, Westbrook was the first player in the history of college football at any level to have 1000 yards rushing and 1000 yards receiving in the same season.
The Falcons' linebackers struggle in pass coverage, which will be a problem when the Eagles send out Westbrook over the middle. While Keith Brooking can play all over the field against the run and the pass, the other Atlanta linebackers are run of the mill, as are safeties Bryan Scott and Cory Hall.
Chris Draft is a good hitter but often doesn't get there in time to make the hit, and at 5-foot-11 he is one of the league's shorter linebackers. That will be an issue because, after Westbrook, McNabb's most dependable receivers are his two tight ends, 6-foot-3 L.J. Smith and 6-foot-6 Chad Lewis. Nobody will confuse Smith and Lewis with Randy Moss -- Minnesota defensive tackle Kevin Williams actually caught Smith from behind last week -- but short tight end routes become even more important in snowy conditions, and Atlanta ranked 27th in preventing successful passes to tight ends. They only intercepted two of them, and they gave up some big games to some mediocre tight ends like Ken Dilger (51 yards and a touchdown) and Kris Magnum (53 yards and a touchdown). Oddly enough, they shut down Tony Gonzalez, but that was because Kansas City was having so much success running that there was no reason to pass.
McNabb is a good pocket passer, but the additional threat of a run gives the Eagles' offense an added dimension. The difference between McNabb and Vick is that McNabb uses the threat of the run to buy time for a pass, while Vick often uses the run because he's not very good at the pass.
McNabb has greatly improved his ability to avoid pressure over the past couple seasons, and now takes about a sack less per game than he did just two years ago. That will be important against the Falcons, whose defensive strength is their pass rush. The Falcons led the NFL with 48 sacks and get almost all their pressure with just the front four, particularly Patrick Kerney and Rod Coleman. The Falcons don't blitz often; when they do, they bring either Brooking or Demorrio Williams, his rookie backup out of Nebraska. Bryan Scott occasionally comes on a safety blitz. Last week, Brooking forced a Bulger fumble on a blitz that was similar to a Minnesota blitz that was missed on a rare error by talented young left guard Artis Hicks, so the Falcons might try this play more often Sunday.
The Falcons pressure is particularly heavy on third downs and McNabb must be careful to never let himself be dropped out of field goal range. (According to DVOA, Atlanta had a below average defense on first and second downs but the fifth-best offense in the league on third downs.) The Eagles will also use screen passes to Westbrook in an attempt to diffuse the Atlanta pressure.
When Westbrook plays receiver, 34-year-old Dorsey Levens takes over as the running back. Last year with the Giants, Levens looked like his career was done; back in Philadelphia, in a familiar offensive system, he has had great success. While Westbrook is more of a boom-and-bust runner, Levens gains consistent chunks of yards. Levens actually had a higher DVOA than Westbrook, and according to our Running Back Success Rate metric, he was successful on 57% of his runs while Westbrook was only successful on 43% of his.
Atlanta's defense got a lot of press in September and October, but their improvement over 2003 somewhat dissipated over the final eight games, in particular against the run. In the first half of the season, Atlanta allowed 3.8 yards per carry to opposing runners, a number that includes the 56-10 loss where Kansas City ran for 271 yards. Over the second half, Atlanta allowed 4.3 yards per carry. With defensive end Brady Smith as the weak link in their run defense, Atlanta was the worst team in the NFL preventing runs to the left. That's where Philadelphia's blocking is the strongest thanks to veteran tackle Tra Thomas and the previously mentioned Hicks.
|DVOA||3.9% (6)||7.4% (3)|
|ATL kickoff||10.1 (6)||-1.6 (20)|
|PHI kickoff||0.7 (15)||15.0 (1)|
|ATL punts||9.6 (11)||-5.2 (16)|
|PHI punts||5.3 (5)||19.3 (2)|
|FG/XP||-3.9 (28)||13.7 (2)|
Last week, Atlanta's Allen Rossum averaged more than 50 yards per punt return, including a 68-yard touchdown. But Rossum's skills will be greatly neutralized this week by a team that has the NFL's best all-around kicking game. They were not the NFL's best in any one facet of special teams, but after adjusting for weather conditions the Eagles ranked number two in punts, kickoffs, and field goal kicking. Both teams have a lot of talented players on special teams besides the kickers and returners, and particularly worthy of mention are Michael Jenkins of the Falcons and Ike Reese of the Eagles.
It is that last skill that may fail the Falcons in the end; Jay Feely is a below-average field goal kicker who is used to kicking in a dome, while Philly's David Akers is comfortable in poor weather conditions.
If this was a seven-game series, it would be almost impossible to imagine Philadelphia losing. But in football we play one game, not seven. Atlanta's inconsistency gives them a shot at winning a single game, and despite their southern origin, snow may actually help their run-oriented strategy. One great play can turn a game, and Michael Vick is the NFL player who most often makes that single great play -- no matter how mediocre his performance in total. But there's a reasonable chance that by the time Vick can make that highlight play, the Eagles will be so far ahead that it won't even matter. Vick will need a great game overall, not just a couple of great plays, to keep Philadelphia from its long-awaited Super Bowl appearance.
*TREND numbers are updated through the playoffs, all other DVOA statistics are regular-season only unless otherwise noted.