ESPN: Wither Leo Mazzone?

I don’t think it’s much of a secret that I think Leo Mazzone is a good pitching coach. It’s been a pretty hot topic on this site for quite a while. In fact, in my book I have a chapter dedicated to the subject. When Mazzone bolted for the Orioles last season, many pundits, like me, expected the O’s pitching staff to improve. But there is no way to spin it, 2006 was not a good year for Oriole pitchers.

Does this mean there is no such thing as the Mazzone effect? That was a question posed to me by an editor at ESPN The Magazine, and in the latest issue (March 12) I search for an answer. In “The Vanishing Magician” I explore Mazzone’s record as a pitching coach, with a particular emphasis on 2006. Some of the reported results I have reported before.

In my upcoming book, I update my previous study on Leo Mazzone’s effectiveness as a pitching coach. This study takes into account aging, park effects, defense, pitcher quality, and the run environment of the league. What I find is that during his years in Atlanta, pitchers who pitched for Mazzone and with another pitching coach had ERAs 0.64 lower with Mazzone than without. How does this happen? Pitchers under Mazzone increase their strikeouts by 10% and lower their home run rates by 20%. I could not find any effect on walks. This is interesting, because it fits exactly with Leo’s advice to his pitchers.

Don’t give into the strike zone. This is about making pitches and trying to execute a good pitch. So forget about walks. And don’t throw one down the middle just because you walked a guy. I’d rather you be off the plate a little than give up a three-run bomb.

Furthermore, when pitchers leave Mazzone, they tend to revert to their old form.

An effect that has persisted for about a decade and a half is unlikely to be a fluke. Still, what about 2006? It’s easy just to say, “hey, it’s a small small sample size, this doesn’t mean much,” because it’s the truth. However, what is the fun in that? 🙂

I looked at pitchers on the O’s and Braves who pitched more than 25 innings with the same team in both 2005 and 2006 to compare how Mazzone’s current and former pitchers performed with and without him. This sample allows me to view pitchers in very similar environments with only the pitching coach changing in both cases. The direction of the stories in both Atlanta and Baltimore are the same: on average Braves and O’s pitchers were worse in 2006 than in 2005. However, the effect on Atlanta pitchers is much larger. Mazzone’s former pupils suffered worse than the men he coached in Baltimore. lending some support to the Mazzone effect.

I can’t reveal more than this, because that wouldn’t be very nice to the good people at ESPN. So, pick up a a copy of the latest ESPN The Magazine or sign-up for a free trial to read the article. This issue features the MLB Fantasy Baseball Preview, which I am enjoying right now.

Given the sum of the evidence, I think Mazzone’s reputation is safe, and I expect he will continue to work his magic over the next few years in Baltimore.

One Response “ESPN: Wither Leo Mazzone?”

  1. Marc says:


    It strikes me that there is something a bit inconsistent about Mazzone’s philosphy on walks. First, even though he talked about not worrying about walks, during their prime the Braves big 3 or 4 didn’t walk many. Glavine was probably the main exponent of the “not giving in to the hitter” philosopy and he consistently had a lot of runners on base. I believe his ERA was generally higher than the others as well. IN general, though, during the peak of the glory years, it seems to me that the Braves k/bb ratios were much better than they were during Leo’s last few years in Atlanta. And the Braves pitchers, particulary Maddux, Glavine, and Smotz, of course, were able to make tough pitches even when behind so that they could not give in and also not walk guys. If you had pitchers that refused to give in but were unable to throw strikes and walked a lot of guys, it seems to me that this philosophy would be less successful. So, the question arises, and exaggerating a bit, did the Braves pitchers succeed because they followed Leo’s philosophy or did the philosophy succeed because the Braves had great pitchers?