Most people have a couple of favorite books that they return to time after time for entertainment or to while away the hours. I also have some favorite books that I like to read again and again. They are action packed, they make me feel good and there’s always something new to discover in them.
My three favorite books: The three Cowboys vs Eagles NFL gamebooks from last season.
As I was leafing through these veritable tomes of statistical goodness, my eyes fell on a stat that I’d regularly overlooked: Field position. Quite often when analyzing stats, the focus is on total offense, total defense, individual player stats etc., stats that can easily become irrelevant if field position is a big factor in a game. So I looked a little more closely at the field position stats for the three games against the Eagles.
Of Philadelphia's 34 possessions, 23 started on or behind their own 20-yard line, including the first nine possessions of the final regular season game. By contrast, the Cowboys started on or behind their own 20-yard line on only 13 of their 35 possessions.
Over the course of the three-game series, the Eagles scored two touchdowns and two field goals on the 23 possessions starting inside their 20. The Cowboys scored 4 touchdowns and two field goals on 13 similarly unfavorable field position possessions. The touchdowns for both teams came at the end of 80+ yard drives. These are hard scores in the NFL.
Life gets a lot easier when a team finds itself in ‘short field’ positions (for the sake of this argument, anything beyond a teams’ own 40 yard line is a 'short field'). Often, these short fields are the result of a takeaway, a long punt or kickoff return, a missed field goal or really bad punting position for the other team. Two things usually happen with a short field: the threat of a score is significantly higher, and the offense often finds itself emotionally charged as a result of the play that set up the short field. As a defense, you don't want that.
Take the Cowboys’ 20-16 victory in the first game against Eagles: The Cowboys got a short field at the Eagles 37 after an interception that set up their first touchdown, a two yard run by Tashard Choice. Another interception in the fourth quarter again set them up with a short field at the Eagles 42 and netted the ‘Boys a field goal. McNabb's failed 4th and 1 attempt set the Cowboys up at their own 45 and four plays later, Miles Austin scores a touchdown to seal the game. Exciting stuff this book, no? I hope I didn't spoil the plot for you.
Over the course of the three games, the Cowboys had thirteen short field possessions and scored on seven of these (four touchdowns, three field goals). The Eagles had three short field possessions and didn’t score on any of them.
This of course got me wondering whether I could show a correlation between field position and game outcomes for a whole 16 game schedule, so I went and downloaded the 2009 NFC East gamebooks (in 64 easy to read volumes). Recommended reading, my friends!
To show that correlation, I needed to calculate field position differential per game. Sound complicated? Not really. Just add up the starting field position of each drive for the Cowboys, then subtract all the starting field positions for, say, the Eagles. Do the same for return TDs or TDs scored directly from a takeaway (because this is yardage that does not show up in field position stats). Add it all up and serve it in a nicely formatted table.
Here's what I found: For the Cowboys, field position differential was an accurate predictor in 88% (14 of 16) of their 16 regular season games in 2009, 75% (12 of 16) for the Eagles and 69% (11 of 16) for the Redskins. The Giants had one tied game in terms of field position, so their result was 14 of 15, or 93%.
Dallas Cowboys Field Position Differential by opponent, 2009
|Yards of field position difference||64||-135||83||36||-180||205||23||160||-69||26
For two Cowboys games, the game outcome doesn't correlate with field position differential. For your reading pleasure, these games are highlighted in yellow. Against Kansas City, a muffed punt and a fumble gave the Chiefs short field possessions on the Dallas 23 and 16, from where they scored a touchdown and a field goal. By all rights, Dallas should have lost that game, but a franchise record 250 yards by saved the day.
Against Denver, the 36-yard difference is slightly skewed by the fact that the Broncos got the ball with one second left on their 2-yard line after two successive incomplete passes to Sam Hurd.
Full set of data for the rest of the NFC East below, but I'm not going to dig through another 400 or so gamebooks for all the NFL data. Not anytime soon anyway ...
Philadelphia Eagles Field Position Differential by opponent, 2009
|Yards of field position difference||102||-236||47||11||10||76||54||-160||-51||10
New York Giants Field Position Differential by opponent, 2009
|Yards of field position difference||-21||135||48||149||90||-48||-116||-54||-11||
Washington Redskins Field Position Differential by opponent, 2009
|Yards of field position difference||21||38||49||-33||-81||-158||-86||-179||4||-26