Tom Brady started in 50 games in which his defense held the opponent to 10 points or less, the highest value among active quarterbacks. Would you be shocked to find out that Tom Brady (and the Patriots) are 50-0 in those games?
As a quarterback, there clearly is a benefit in playing for a team with a strong defense, as other NFL QBs and their W/L records will attest. Peyton Manning is 36-0 when the opponent scored 10 points or less, Joe Flacco is 32-0, even Eli Manning is unbeaten at 30-0, and there are many more QBs who have never lost such a game. Most of the remaining QBs in the league today have not lost more than such game, Ben Roethlisberger for example is 48-1 in those games. In fact, of the currently active QBs in the league only two QBs have lost more than one game when the opponent was held to 10 points or less: Jay Cutler lost two, Mark Sanchez lost four.
The reality is, it's hard to lose a game where the opponent is held to below 10 points. Yet if you were to read some of the headlines floating around after gameday - and if you were to give those headlines any credence - you could easily get the impression that it was the superstar QB all by himself who won those games.
The QB, whether you like it or not, is the only player on a football team who has a W/L record in his personal stats. But that doesn't mean the QB is actually winning games for his team. Teams can win games with a strong defense and a good ground game despite the QB, yet the QB will get the win on his record.
Which is why today we'll take a more objective, stat-based look at the W/L records of NFL QBs and try to figure out which NFL quarterbacks are winning games for their teams, and which aren't. To do that, we'll look at 'wins over average' to understand which offenses, and by extension their QBs, contributed to wins for their teams.
In addition to the more established QB metrics like passer rating, ESPN's QBR or Football Outsiders' DVOA, I also like to take a look at metrics that are not as ubiquitous and as familiar. Last week for example, I wrote about a QB metric called Passer Rating Index, I've written extensively about Adjusted Net Yards per Pass Attempt (ANY/A), EPA, WPA and many more. I do this not because I think they are necessarily better metrics than the ones we use more frequently, but because I believe that some of the metrics that are a little off the beaten path help us get a more complete and perhaps more nuanced picture of QB performance than the more established metrics alone can, and 'Wins over average' (WOA) just such a metric.
WOA was developed by Doug Drinen at Pro-football-reference.com (PFR) in a post on adjusting QB records. I've taken his approach and modified it slightly for this post. The underlying assumption for WOA is that it's a lot easier for a QB to win games when the defense holds the opponent to 10 points than it would be if the defense gave up 30 points.
What WOA does is it calculates a QB's winning percentage against a given bracket of points scored by the opponent (e.g., 0-10 points, 11-17 points etc.) and then compares how many games a given quarterback won versus how many games an NFL-average QB would have been expected to win.
To calculate WOA, we first need a baseline to determine what 'NFL average performance' looks like. For our purposes here we'll use the four-year league average winning percentage in regular season games between 2011 and 2014. In the table below I've crunched the regular season number for all NFL teams for the last four years, excluded tied games, formed five clusters by points allowed, and looked at the winning percentages for each cluster.
|2011-2014||QB Record versus Points Allowed|
How to read the table: A QB (and by extension, the team) will almost always win the game when the defense holds the opposing team to 10 points or less (258-7 winning record). The NFL average winning percentage is .974 against the '0-10' points bracket. The more points a team allows, the lower their chances of winning the game. When your defense allows 32 points or more, your QB's chances of winning the game are very low (.099 winning percentage, 36-326 record).
What separates the good from the merely average QBs is their ability to win games that an average QB would not win. And that is exactly what WOA measures. We'll use Tony Romo's 123 career starts to further explain the concept.
|Tony Romo's Wins Over Average versus Points Allowed
|Wins Over Average||-0.4||+1.3||+6.4||+2.8||+0.8||+10.7|
Tony Romo and Wins Over Average: Tony Romo has a record of 23-10 as a starter in 33 games when the defense allowed between 18 and 24 points. The average NFL QB would be expected to win 16.6 of those games (33 games x .504 NFL average), so Romo has delivered +6.4 wins over average in this points bracket. In the 11-17 points bracket, Romo has a 20-4 record in 24 games, an average NFL QB would be expected to win 18.7 games (24 games x .779 NFL average), Romo therefore gets +1.3 WOA. Across all brackets, Romo has accumulated +10.7 WOA as per the table above.
So statistically, over the course of his nine years as a starter, Tony Romo accounted for almost eleven more wins for the Cowboys than an average NFL quarterback would have. At first glance, that doesn't sound like all that much, so in the next step we'll try to understand how that number compares to other quarterbacks around the league.
Before we do that though, keep in mind that when I say "Tony Romo", I'm actually talking about Dez Bryant, DeMarco Murray, Jason Witten, the offensive line, Jason Garrett, Scott Linehan and many more people who make up or influence the Dallas Cowboys offense. Quarterbacks don't win or lose games, teams do. But if quarterbacks are going to be measured by wins, let's at least make sure we understand the quality of those wins.
In the next table, I've listed the 29 projected starting quarterbacks and 12 backups with the most career regular season starts. I've calculated their Wins Over Average in the same way I calculated Romo's numbers above. Since every QB on the list has started in a different number of games, I've added an additional column in which I divided the WOA by the total number of regular season games started. This should allow for a better comparison of the quarterbacks, regardless of how many games they started.
Career Wins Over Average by Quarterback, regular season games
|QB||Team||W/L Record||Wins Over Average||WOA in %|
|Projected Starting QBs with less than 30 starts|
No real surprises at the top, where Tom Brady, Peyton Manning and Aaron Rodgers are in a class of their own. A surprise here is clearly the third-ranked Andrew Luck. In his three years in the league, Luck has averaged an 86.6 passer rating, which is far below that of Manning, Brady and Rodgers over the same span, yet Luck (and his offense) has been winning a lot of games for the Colts. The combination of average passer rating and above average WOA suggests that the Colts have been winning more games than Luck's performance as a pure passer would warrant, and maybe that's part of his appeal: He's not a great passer (yet) but he and his team have consistently found ways to win like great QBs and their teams do.
Russell Wilson in some ways is the exact opposite of Andrew Luck. He has an above average three-year passer rating of 97.8, but that hasn't translated into Wilson (and the Seahawks offense) getting a lot of wins over average. As we saw in last week's post on offensive and defensive contributions to winning games, the Seahawks win games primarily via their defense, and as long as the offense doesn't lose them any games, they'll be fine. And if their offense puts up gaudy stats in the process, so much the better, but it doesn't really have a big overall impact.
But back to our ranking: After the top four QBs with double digit WOA percentages there's a second tier of above average QBs (Romo, Brees, Ryan, Rivers) who can all play spectacularly at times but are also prone to inconsistent performances. This group is so tightly bunched that a single win in a shootout or a loss in a low-scoring game could rearrange the order completely.
There's a considerable gap between this second tier group and a nine-man group of slightly above average QBs who have a positive WOA value. This third tier of QBS may not win their teams a lot of games, but at least they aren't losing too many either, at least as measured by WOA.
This third tier (and a positive WOA%) also marks a demarcation line of sorts. Of the 17 QBs with a positive WOA percentage, only two (P. Manning, Cutler) are not with their original teams anymore, and most of these 17 QBs could probably be described as franchise QBs.
Of the seven QBs with a negative WOA percentage, only two (Newton, Tannehill) remain with their original team, and while Newton and Tannehill also deserve the 'franchise QB' label for now, I'm not sure any of the others do.
The first group of 24 projected starters is followed by five more projected starters who have less than 30 starts to their name. With stats like WOA, we quickly run into sample size issues with low career start totals. But I wanted to include them anyway, because Nick Foles is particularly noteworthy in terms of WOA. Consider that he has a higher WOA in 24 starts than a guy like Joe Flacco has in his 112-game career. But like the other (mostly young) QBs in this group, he'll have to show that he can win games consistently over a longer period, or they'll all be relegated to the final group, the backups.
This final group contains the journeymen of the NFL, most of whom have already played for multiple teams and are cling to their roster spot by a thread.
Obviously, there are many ways to evaluate a QB's performance. This is one way that you probably haven't seen much of before, but taken with other valid metrics out there, I hope it helps solidify an overall picture of today's NFL quarterbacks, and perhaps raises a question or two.