Mazzone Magic:
How much does a pitching coach matter?
January 1, 2006


Over the last decade or so, the Atlanta Braves have enjoyed a level of success few teams in professional ever sports have.  There are a number of factors that have contributed to their 11 consecutive division titles – GM John Schuerholz’ shrewd acquisitions, manager Bobby Cox’s steadying hand, a spectacularly good scouting department that has provided a wealth of talent – but the reason most often cited is the influence of pitching coach Leo Mazzone.  During his tenure, the Braves have finished first or second in ERA nearly every year and have had multiple Cy Young award winners.  But how much of that success was due to Mazzone?

JC Bradbury completed a study that revealed that pitchers who come to him generally lower their ERA: starters by about a third of a run, relievers by around seven tenths.  That is a remarkable achievement by itself, but it doesn’t really tell how significant that it really is.  After all, it doesn’t compare Mazzone to any of his contemporaries; it only looks at one pitching coach. 

So I thought I’d see how well Mazzone compares.  However, I decided a different approach was needed.  Although ERA is more trustworthy than a stat like wins, it does have a few drawbacks, especially with regard to relievers.  Relief ERA isn’t a very good indicator of how well or poorly a pitcher did.  Not only do they suffer from a small sample size – generally 40-80 innings per season – but relievers are generally used only when the situation is ideal for their skills.  For example, lefty specialist Chris Hammonds’ good ERA is due to being used almost exclusively against left-handed hitters.  A reliever’s ERA is largely dependent on how the manager uses him and not necessarily due to any instruction from the pitching coach.  A starter’s ERA is likewise affected as he has no control over whether any inherited runners he leaves score or not.  If he’s backed by a good bullpen, his ERA benefits.  If not, it suffers.  But the pitching coach has little or no effect in that regard.

With those concerns in mind, I decided to limit my study to just starters.  While it’s rare relievers are converted to starters, it does happen enough to include, so I limited those cases to relievers who have made at least 10 starts under at least two different pitching coaches.  I also decided to use baserunners allowed instead of ERA.  In my view it removes the effect of the bullpen and it limits the manager’s decisions as a factor.  I also limited the study to current pitching coaches – those who held the post as of last season - who had at least three years experience on the job.  Ultimately, three years was an arbitrary choice but it seemed like it would be enough time to mitigate any completely terrible or totally awesome seasons by a single pitcher. 

For the study itself I compared each pitcher’s WHIP to not only what he himself had done under other pitching coaches, but also how his performance compared to league average.  In this way, a pitching coach who benefited from a smart GM who kept him supplied with above average talent wouldn’t have an advantage over a pitching coach who toiled for a GM who was penurious and/or soon to be fired. 

One factor I did not include was park factor, for two reasons.  The first is that I wasn’t able to locate any reliable breakdowns of how parks affected hits and walks before 1993.  I could find the overall effect on run scoring, but that doesn’t necessarily correspond with the hits and walks effects.  For example, Busch Stadium has played largely as a neutral park for run scoring, but is actually one of the better parks for hits in general.  The other reason is that I’m not entirely satisfied that park factors accurately compensate for the unbalanced schedule.  The NL East is home to three of the best pitcher’s parks – RFK, Pro Player and Shea – so it isn’t much of a surprise that those teams fare poorly in the run scoring breakdowns because they play a majority of their road schedule in tough places to score.  Besides, if I included them I wouldn’t have anything to work on next offseason.  Just joking, of course. 

Anyway, the results were interesting.  Mazzone fared very well, topping the list of 19 coaches by improving the average starter by more than 10%, an astounding feat.  However, his charges were on average nearly 3.5% better than the average talent before they came to the Braves, so it’s not as if he was turning sow’s ears into silk purses.  Still, his measure of success was greater than that of any other pitching coach.  Or was it?

There was on other factor that Mazzone had that no other pitching coach enjoyed.  A secret weapon, if you will: Greg Maddux.  No other pitching coach had the benefit of having a Hall of Fame star for as long or under the ideal circumstances that Mazzone did.  Maddux came to the Braves after winning his first Cy Young award just as he was entering his prime years and stayed in Atlanta for 11 seasons.  When he started to show signs of decline, the Braves let him walk via free agency.  Mazzone was the beneficiary of Maddux’s best years and endured none of his growing pains or decline.  If there’s any pitching coach that deserves credit for what Maddux developed into, it’s probably his Cubs pitching coach, Billy Connors. 

Not since Casey Stengel and Whitey Ford has a pitcher of Maddux’ caliber spent as much time with one pitching coach.  Most of the time it was due to the manager and his staff being fired due to the team’s poor performance.  But it’s also not uncommon for pitchers like Roger Clemens, Randy Johnson and Pedro Martinez to get traded or allowed to go to another team on their own.  Mazzone had Maddux for 73.3% of his 15-year tenure in Atlanta.   The closest any other coach came was Ray Miller, who had Jim Palmer for seven of his 19 years (37%) but Palmer was clearly in decline for three of them. 

Neutralizing the Maddux effect by removing him from the equation yields a more accurate picture of Mazzone’s ability.  He’s still one of the best pitching coaches in baseball but it’s clear that we don’t have to open a new wing at the Hall of Fame just for him any time soon.  What is most surprising is how well some lesser known pitching coaches like Bryan Price, Mike Maddux and Jim Colborn compare.


Pitching Coach          coached    uncoached    diff
Leo Mazzone             1.107      1.033       0.074
Bryan Price             1.055      1.001       0.054
Mike Maddux             1.026      0.973       0.053
Jim Colborn             1.074      1.024       0.050
Dave Righetti           1.018      0.983       0.035
Randy St. Clair         1.032      0.997       0.035
Dave Duncan             1.026      0.999       0.027
Mazzone (w/o Maddux)    1.054      1.027       0.027
Rick Anderson           1.072      1.045       0.027
Rick Peterson           1.071      1.045       0.026
Don Gullett             1.020      0.998       0.022
Don Cooper              1.069      1.047       0.022
Ray Miller              1.053      1.031       0.022
Dave Wallace            1.088      1.067       0.021
Mark Connor             1.071      1.051       0.020
Vern Ruhle              1.036      1.028       0.008
Larry Rothchild         1.046      1.040       0.006
Mel Stottlemyre         1.070      1.071      -0.001
Bud Black               1.019      1.030      -0.011
Bob Apodaca             0.939      0.951      -0.012


Before anyone gets their panties in a wad I want to emphasize that this is looking at only one aspect of what a pitching coach does.  In my view, there are three things a pitching coach is charged with.  The first is keeping his pitchers healthy.  The second is developing the prospects from his own organization and the third is getting the most out of the pitchers his team acquires.  So it’d be a mistake to look at this breakdown and conclude that Bud Black isn’t a good pitching coach.  One only needs to look at the development of John Lackey and Ervin Santana to understand where his strengths lie.  Conversely, Dave Duncan hasn’t done such a great job of developing talent in Oakland or St. Louis. 

Looking at Mazzone, his record for keeping pitchers healthy is probably no better than average.  Remember, John Smoltz has had three arm surgeries, and both Odalis Perez and Mike Hampton have had reconstructive surgery after pitching for him.  His reputation for keeping pitchers healthy appears to be based largely on two extraordinary starters, Maddux and Tom Glavine.  His record with young pitchers isn’t as good.  Steve Avery was never the same after a huge number of innings at an early age, and Jason Schmidt, Jason Marquis, Odalis Perez, Paul Byrd and Bruce Chen have all blossomed only after leaving Mazzone.

So what does this mean from a fantasy perspective?  First it means that we shouldn’t necessarily jump on the Baltimore bandwagon now that Leo is there.  Ray Miller was a pretty good pitching coach and Mazzone’s record with young pitchers isn’t all that great.  If the Orioles do enjoy a renaissance this year, it could be as much due to replacing Javy Lopez behind the plate with Ramon Hernandez as anything Mazzone does. 

The second thing to take away is that it wouldn’t be surprising to see the Diamondbacks and Pirates enjoy strong performances from their pitching staffs because Bryan Price and Jim Colborn are very good pitching coaches.