Naivete Shattered, Deflategate Reconsidered..

Yesterday I wrote about Deflategate as a non issue and was questioned by several of you. One guy called my piece an example in “nerdiness.”. fThank you, I think.

I have now reconsidered as I really didn’t think anything was amiss. Now I am forced to reconsider my position.

I erred on the balls issue, It seems that each quarterback has balls prepared to his liking before each game. I thought that a dozen balls were prepared and given to the officials before the game like in baseball where the umpires prepared the balls by rubbing Delaware River mud on them. Now I learn that each team supplies a dozen balls for its use, only. This is like allowing the pitchers in baseball to prepare the balls they will use. Just imagine the ingenious application of various substances that would occur there. I am sure some sticky stuff finds its way to the footballs in this case, and, I imagine, that the balls are inflated to the minimum legal limit by some teams to allow temperature to take effect later. That does occur, apparently.

The most shocking article sent to me is the following that deals with the Patriots apparent success in not losing fumbles at home. If you are a conspiracy minded person and think Coach Belichick capable of such subtle thinking, read this one. Just to spike interest, read the following quote and then the article.

“Ironically, as my study yesterday showed, the Patriots performance in wet weather home games mysteriously turned ridiculous starting in 2007.  In 2006, they went 0-2.  From 2007 onward, they went 14-1.”

Now, read on and I am sorry for the misleading post yesterday, nerdi as it was.

The New England Patriots Prevention of Fumbles is Nearly Impossible

By Warren Sharp

After reading this piece, be sure to review the follow-up article, which looks at individual player data for New England Patriots when playing on other NFL teams.

QUICK NOTE: The analysis at the TOP looks at fumbles LOST. Further down, I look at ALL fumbles, regardless of who recovered.

Yesterday I investigated whether or not the New England Patriots outperform expectations in bad weather.  I had several recommendations to look at home and road data, as opposed to just home data.  Mulling whether or not to undertake that further (time consuming) analysis, I watched this video:

I immediately noticed something that cannot be overlooked: the issue with ball security and fumbles.  Then I remembered this remarkable fact:

The 2014 Patriots were just the 3rd team in the last 25 years to never have lost a fumble at home!  The biggest difference between the Patriots and the other 2 teams who did it was that New England ran between 150 and 200 MORE plays this year than those teams did in the years they had zero home fumbles, making the Patriots stand alone in this unique statistic.

Based on the desire to incorporate full season data (not just home games, as a team theoretically bring “doctored footballs” with them on the road) I performed the following analysis:

I looked at the last 5 years of data (since 2010) and examined TOTAL FUMBLES in all games (as well as fumbles/game) but more importantly, TOTAL OFFENSIVE PLAYS RUN.  Thus, we can to determine average PLAYS per FUMBLE, a much more valuable statistic.  The results are displayed in the chart below.  Keep in mind, this is for all games since 2010, regardless of indoors, outdoors, weather, site, etc.  EVERYTHING.

(click to enlarge)

One can CLEARLY SEE the Patriots, visually, are off the chart.  There is no other team even close to being near to their rate of 187 offensive plays (passes+rushes+sacks) per fumble.  The league average is 105 plays/fumble.  Most teams are within 21 plays of that number.

I spoke with John Candido, a Data Scientist at ZestFinance who I know from work on website, and sent him the data.  He said:

Based on the assumption that fumbles per play follow a normal distribution, you’d expect to see, according to random fluctuation, the results that the Patriots have gotten over this period, once in 16,233.77 instances”.

Which in layman’s terms means that this result only being a coincidence, is like winning a raffle where you have a 0.0000616 probability to win. Which in other words, it’s very unlikely that it’s a coincidence.

I actually went back and researched 5 year periods for the entire NFL over the last 25 years. The Patriots ratio of 187 plays to 1 fumble is the BEST of ANY team in the NFL for ANY 5 year span of time over the last 25 years. Not was it just the best, it wasn’t close:

  1. 2010-2014 Patriots:  187 plays/fumble
  2. 2009-2013 Patriots:  156 plays/fumble
  3. 2006-2010 Colts:  156 plays/fumble
  4. 2005-2009 Colts:  153 plays/fumble
  5. 2007-2011 Patriots:  149 plays/fumble
  6. 2008-2012 Patriots:  148 plays/fumble
  7. 2010-2014 Texans:  140 plays/fumble
  8. 2004-2008 Colts:  139 plays/fumble
  9. 2006-2010 Jets:  135 plays/fumble
  10. 1999-2003 Chiefs:  134 plays/fumble

There are a few key takeaways.  First and foremost, the 187 plays/fumble dwarfs even the rest of the best seasons the last 25 years.  Second, the Patriots have been at the top of the NFL since 2007.

Ironically, as my study yesterday showed, the Patriots performance in wet weather home games mysteriously turned ridiculous starting in 2007.  In 2006, they went 0-2.  From 2007 onward, they went 14-1.

The next obvious question becomes, where were the Patriots in this statistic pre-2007?  Take a look:

(click to enlarge)

As you can see, the Patriots won their Super Bowls having a below average rate of fumbles lost given today’s average of 105 plays/game.  But in 2007, something happened to propel them to a much better rate (you’ll remember, that just so happened to be the same year they went 16-0 in the regular season).  But even looking at these numbers, its clear how insane the 187 number is:  they are almost running 100 MORE plays without a single fumble as compared to the 2002-2006 period when they won 2 of their 3 Super Bowls.

To further illustrate how these numbers are astonishing, the below graphics lay out clearly how far off the Patriots are from the rest of the league.  Its evident to the eye how far removed they are from the norm.  Whether we look at a histogram laying it out, where the Patriots and their 187 plays/fumble is far from the “bell shaped curve”:

(click to enlarge)

or the same chart as above, this time displaying color bands as we move away from the 105 plays/fumble average.  You can see the darker red band contains all teams but the bottom 3 and the top 3, and that the bottom 3 are very close to the darker red band.  Meanwhile, the Patriots are really in a league of their own:

(click to enlarge)

Could the Patriots be so good that they just defy the numbers?  As my friend theorized:  Perhaps they’ve invented a revolutionary in-house way to protect the ball, or perhaps they’ve intentionally stocked their skill positions with players who don’t have a propensity to fumble.  Or perhaps still, they call plays which intentionally result in a lower percentage of fumbles.  Or maybe its just that they play with deflated footballs on offense.  It could be any combination of the above.

But regardless of what, specifically, is causing these numbers, the fact remains:  this is an extremely abnormal occurrence and is NOT simply random fluctuation.


UPDATE: It was suggested that I look at ALL fumbles, not just fumbles lost.  With that said, let’s look there:

First, it should be noted (as the tables above show) that teams playing indoors fumble the ball less frequently.  Reasons are many, foremost the ball won’t be wet from precipitation, damp from late night condensation, and a variety of other reasons.  Which is why, if you look at the very first chart I posted above, you’ll see the teams who fumble the MOST/play are generally colder weather teams who play outdoors (PHI, DEN, BUF, PIT, WAS, NYG, KC, NYJ).  Whereas at the other end of the spectrum, aside from the Patriots in their own world, are HOU, ATL and NO, all dome teams.

The below graphic looks at ALL fumbles over 5 year periods the last 25 years.  I planned to cut this off at JUST the top 10 teams, but all we would have seen were the Patriots and dome teams.  Top 15 would have accomplished the same.  So I had to expand to the top 25 team periods.  As you can see, of the top 25 team-periods, 17 are dome teams, including 11 of the top 15.   First, let’s look at the chart, then we’ll look at comparisons to average:

(click to enlarge)

As is apparent, the Patriots are the only outdoor NFL team the last 25 years to average 70 plays/fumble or better, and they did it from 2007-2014 (four, five year periods).  Its simply uncanny, as the statistics above similarly showed.


  • Over the last 25 years, indoor teams averaged 43 plays/fumble (in all games they played that season, regardless of site, understanding that half their games would be played indoor sans-weather).
  • Since 2000, they improved to 46 plays/fumble.
  • Over the last 25 years, outdoor teams averaged 41 plays/fumble.
  • Since 2000, they improved to 43 plays/fumble.

The Patriots averaged 73 plays/fumble the past 5 years, almost 70% better than the 43 plays/fumble that outdoor teams averaged since 2000.

Next, lets look only at the current 5 year period:

The league average plays per fumble from 2010 thru 2014 was 50 plays/fumble.

  • For indoor teams, the average was 55 plays/fumble.
  • For outdoor teams, excluding the Patriots, the average was 46 plays/fumble (9 fewer).

The Patriots averaged 73 plays/fumble, almost 60% MORE than outdoor teams, and almost 50% MORE than the league average the past 5 years.

(click to enlarge)

Since we now can clearly in the data, both near term and long term, that dome-based teams (who play at least 8 games out of the elements) have an advantage in the fumble department, we can exclude them from comparisons to the Patriots.

If we do, I can produce a chart identical to the one at the very top which looked ONLY at fumbles lost.  This one looks at ALL fumbles, whether lost or recovered.  I think the point still remains:

(click to enlarge)

If this chart looks nearly identical, it should.  The Patriots are so “off the map” when it comes to either fumbles or only fumbles lost.  As mentioned earlier:  this is an extremely abnormal occurrence and is NOT simply random fluctuation.


Warren Sharp of is an industry pioneer at the forefront of incorporating advanced analytics and metrics into football analysis. A licensed Professional Engineer by trade, Warren applies the same critical thought process and problem solving techniques into his passion, football. After spending years constructing, testing and perfecting computer models written to understand the critical elements to win NFL football games, Warren’s quantitative analytics are used in private consulting work, and elements of which are publicly shared on To contact Warren, please or send a direct message on Twitter to @SharpFootball.



Deflategate Explained; Lessons From An Old Audi

On Sunday January, 18, 2014 the New England Patriots trounced the Indianapolis Colts 45-7 in the AFL Conference Championship Game that determined which of them would play in the Super Bowl. Such a drubbing promoted claims of cheating to alleviate the sense of inadequacy such a defeat engenders in the vanquished. Furthermore, New England’s Coach Belichick (and Tom Brady, to a lesser degree) is an easy target as he is known to have played loose with the rules before.

The claim is that Belichick, or some designee, inflated the balls 2 lbs below the 12.5-13.5 psi required under the rules. Apparently, such under-inflation produces a ball that is easier to grip in colder or wetter conditions. The Patriot’s scheme, it is said, was to make it easier for Tom Brady to pass the ball, but it seems Indianapolis’s Andrew Luck also benefitted from the softer ball as his Colts scored their touchdown in the second quarter with the softer ball. that presumes the Colts balls were deflated as well. Nevertheless, both teams played with legal balls in the second half.
In fact, after the properly inflated balls entered the game in the second half, the Colts were shut down and the Patriots scored 21 points in the third period alone.

The pressure in a football, a tire, or balloon, for that matter, is a relative figure that relates to pounds per square inch over the relevant atmospheric pressure;  more air in New Orleans, less in Denver. Also, temperature has significant inluence over PSI. Pressure goes up in the heat and down in the cold.
So how does this relate to my old Audi, which happens to have been a 1983 5000 Turbo, a magnificant car? However, this car had mag wheels that were impacted by cold to a high deegree that resulted in flat tires in extreme colld. This was due to the loss of tire pressure holding the tire to the shrinking wheel. On cold days the first year I had the car, and I mean -20 f cold,  I would find a tire flat at the worst time, such as after leaving a restaurant at 10:00PM. Changing the tire was a challenge. To avoid such dilemma, I learned that for each ten degree drop in temperature, I could expect a 1 pound drop in tire pressure. This is not a huge problem unless the tire/wheel combination didn’t work well together, as was the case with my car. I just over-inflated the tires.

The rule here, however, gets to the “deflategate” issue. If the balls were inflated in a 72 degree in a locker room and then were moved to a 50 degree field, maybe a 1 to 2 pound change could occur. If the Patriots actually preferred the 12.5 psi pressure, then the ball may read 11.5 later, or 10.5, which it was due entirely to temperature.  The effect on play, however, would be positive for both teams as it seems the softer ball is easier to handle on cold, wet conditions, as it was in Foxboro that Sunday evening. Maybe the NFL should adopt inflation rules for different weather conditions, softer for wetter, for example.

I play tennis in the North, so that means lots of early and late season matches in cold weather. I love hitting the ball then as it doesn’t fly long. I can swing with impunity and it stays inside the lines, a beautiful thing! Now, with the knowledge gained from “deflategate,” I can blame long shots in August on the weather. (Tennis balls are manufactured with 14lbs of pressure.)

Back to the NFL. Each team provides 12 balls, or maybe 20, for the game. These balls are all “broken in” by equipment men who bang them around so that they soften to the touch. (The same process takes place in the NBA, by the way) The league also has 8 balls sent directly from the manufacturer to the game officials at the stadium for kicking, not to be adulterated by the the teams. (My high school, had one “game ball” that was kept in the coach’s office during the week, only to be used on Friday!)

So, after considering the evidence, “deflategate” is much ado about nothing and is merely a conjured story to fill the dull week between the conference chamionship game and the Super Bowl next week. It is also designed to give some comfort to the Indianapolis Colts who got their butts kicked by the vastly superior Patriots in Foxboro that Sunday evening. Better to blame the ball than recognize your own lack of skill. Enough said.