A Closer Look at The Career Quarterback Ratings of Peyton Manning and Tom Brady

Since the 2007 season, a lot has been made by many of Tom Brady’s fans about career quarterback rating.  It is no coincidence of course that career quarterback rating suddenly became meaningful to the conversation after Tom Brady’s jumped from 88.4 to 93.0 in the course of a single season (currently 92.9 after 11 pass attempts in 2008). 

Suddenly, Brady’s career quarterback rating of 92.9 looks a lot more similar to Peyton Manning’s career quarterback rating of 94.7. 

After all we are now talking about a relatively marginal difference of 1.8 rating points. While I, as a Colts fan, am willing to admit that the difference of 1.8 rating points isn’t a very big margin, I do feel that those career averages are quite misleading for a number of reasons. 

Before I get into those reasons though, let me say up front that I do not consider quarterback rating to be a very good rating system to begin with since it does not take sacks or fumbles into consideration and in my opinion places too much emphasis on completion percentage at the expense of better statistics like yards per attempt.

So why would I argue that Brady and Manning’s career quarterback rating averages can be misleading? 

Well for starters, Peyton Manning started from day one as a rookie while Tom Brady had the luxury of learning from the bench for a year before getting thrown to the wolves.  Clearly, the difference between a rookie quarterback and simply first year starter is tremendous. 

Just ask guys like Carson Palmer, Phillip Rivers, and Aaron Rodgers, who had very strong numbers in their first years starting after benefiting from years of experience on the sideline. 

I remember people being extremely impressed with big first years from true rookie quarterbacks like Ben Roethlisberger and Matt Ryan, but I don’t recall the same kind of acknowledgement and wonder when it came to Palmer, Rivers, and Rodgers. 

There’s a reason for that obviously: one is much rarer and difficult of an accomplishment than the other. 

While Manning did set a handful of rookie passing records including those for completions, passing yards, and passing touchdowns, obviously his 71.2 quarterback rating as a rookie is not representative of his career. 

If you’re still not convinced, consider that Brady’s QB rating remained very consistent for his first three seasons as a starter (86.5, 85.7, 85.9) while Manning’s skyrocketed in his second and third year (71.2, 90.7, 94.7). 

Thinking a player like Manning, who has such a reputation for film study and preparation, would not have benefited from an extra season to learn on the sideline is just preposterous.

Manning’s career veteran quarterback rating is 97.3 compared to his own career quarterback rating of 94.7 and Brady’s career veteran quarterback rating of 93.0.

Another problem with career quarterback rating, which becomes even more troublesome when comparing players from entirely different eras, is the realization that league averages for QB rating change over time. 

One notable point in recent history has occured since the 2004 season. 

It was during the offseason prior to the 2004 season that the league’s referees were asked if they had been enforcing the rule about no contact with a receiver past five yards any differently as of late. 

A drop in offensive production was noticed and the league’s officials admitted that they were not enforcing the rule the same way as they have in the past, which included after the rule was similarly re-enforced in the 1990's. 

The rule was re-enforced and 2004 became a banner year for passing with quarterbacks benefiting from the re-enforcement ever since. 

Another such trend goes back to the 2007 season and continues through the present.  Offensive holding penalties have been called significantly less since the 2007 season compared to seasons prior.

The reason for this according to the league’s referees is that they are now only calling offensive holding on plays that according to their judgment are ones in which the infraction would have affected the outcome of the play. 

There are plenty of other minor changes that affect statistics across the league, such as new balls being used on every kickoff reducing the distance of kickoffs, but the point is that statistics change over time so it is unfair to penalize one player for playing a greater percentage of his career during more difficult times.

Manning’s career quarterback rating since 2004 is 103.5 while Brady’s since 2004 is 98.0. 

Since narrowing the selection to since 2004 increases the concentration of Brady’s time with Randy Moss while decreasing the concentration of Manning’s time with a productive Marvin Harrison, it almost seems counterintuitive that Manning’s relatively narrow 1.8 point advantage in career QB rating would more than triple to a 5.5 point advantage since 2004. 

Additionally, if we narrow the selection to prior to 2004, Manning’s we still see an increase in Manning’s advantage from 1.8 to 2.2 even with his rookie season included. 

It might seem odd that Manning could have greater advantages in both splits than he does overall, but that is the odd effect that Brady having played a larger percentage of his career since 2004 creates.

Another issue with career quarterback rating is the fact that Brady’s record setting 2007 season represents a significantly higher proportion of his career rating than Manning’s record setting 2004 season does for his career rating. 

While I’m sure both sides would love to think that their quarterback is going to produce another such season, most likely neither will ever come close to reaching those statistical heights again. 

Statistically speaking, those special seasons are really just outliers. While removing those special seasons from each quarterback’s career QB rating should hurt Manning in the sense that his 2004 season was rated 3.9 points higher than Brady’s 2007 season, it is clearly not the case. Manning’s more marginal 1.8 point advantage in career QB rating more than doubles to an advantage of 5.1 points.

Manning’s quarterback rating excluding 2004 is 92.4 while Brady’s excluding 2007 is 88.3.

The final issue with career quarterback rating that I will discuss once again deals with proportion. While Manning’s two best seasons of 2004 and 2005 were also the two seasons with the fewest pass attempts in his career, Brady’s best season of 2007 was the season with the second most pass attempts in his career. 

Additionally, two of Manning’s worst seasons, his rookie season of 1998 and 2002, were the two seasons with the most pass attempts in his career. 

Should Peyton Manning’s rookie season account for a greater proportion of his career quarterback rating than either of his best seasons of 2004 and 2005? 

Does it make sense that Peyton Manning’s career quarterback rating should drop because the Colts sent in his backup Jim Sorgi when Manning’s success put games and the season away early? 

I don’t believe either of those to be valid reasons. 

To address this issue, I will weight each full season of Peyton Manning and Tom Brady’s careers evenly.  Obviously Brady’s 2000 and 2008 seasons will just be thrown out since he played less than a quarter in each (both season ratings are below his career average anyway).

Manning’s evenly weighted career QB rating is 95.2 while Brady’s is 92.6.

So to summarize the various issues we explored, it seems sensible to combine some of these different ways of looking at Peyton Manning and Tom Brady’s quarterback rating.

We can exclude Manning’s rookie season while accounting changes in rule enforcement since 2004 and evenly weight full seasons to create what I consider to be a more relevant and representative quarterback rating for each player.

Manning’s evenly weighted QB rating since 2004 is 103.8 while Brady’s is 97.5.

Furthermore, we can throw out each quarterback’s special record breaking season and compare their ratings since 2004 without them and of course evenly weighted.

Manning’s evenly weighted QB rating since 2004 with his 2004 season excluded is 99.5 while Brady’s with his 2007 season excluded is 90.9.

That’s a difference of 8.6 rating points. That’s obviously quite different than a difference of 1.8 rating points.