Mathis vs. Napoli

Los Angeles Angels of Anaheim manager Mike Scioscia knows a thing or two about catching. Scioscia crouched behind the dish for the Los Angeles Dodgers from 1980-1992, and by all accounts, he was a skilled defender. According to Sean Smith‘s Historical WAR data, Scioscia saved 38 runs compared to an average catcher during the course of his career.

Given his background, it’s no surprise that Scioscia puts great emphasis on the defensive virtues of his catchers. His two current options, Jeff Mathis and Mike Napoli, have polar opposite reputations regarding their glove work. Mathis is praised for his defensive skills, while Napoli is panned for his problems behind the plate.

Last year, Napoli started 84 games for the Angels, while Mathis started 78 times. We’re just four games into the 2010 season, so it’s probably best not to make too much out of playing time patterns. But Mathis has started three games to Napoli’s one. With Hideki Matsui occupying the DH spot on most nights, Napoli’s potent lumber could gather dust if Scioscia continues to prefer Mathis at catcher. Is Scioscia’s decision costing the Angels runs?

Mathis and Napoli couldn’t be much different as far as catchers are concerned, with the former a “catch and throw” guy with a slack bat and the latter a questionable defender with an offensive profile that far surpasses most others who don the tools of ignorance (the average catcher hit .254/.320/.395 in 2009).

ALCS Game 5: New York Yankees at Los Angeles Anaheim

First, let’s start with the offense. The 27 year-old Mathis showed some potential with the stick in the minors in favorable offensive environments, but he holds a career .202/.277/.324 line in the majors, with a .265 wOBA. Mathis draws some walks (his 8.5 BB% is right around the MLB average), but he has limited power and struggles to make contact. There’s a consensus among the projection systems that Mathis is a poor hitter, even by the modest standards of the position that he plays:

CHONE: .283 wOBA
ZiPS: .286 wOBA
Oliver: .263 wOBA


Napoli, by contrast, has mashed to the tune of a .256/.357/.491 triple-slash in the majors, good for a .363 wOBA. His secondary skills are superb for any hitter, much less a catcher. Napoli has walked in 12.2 percent of his plate appearances, while posting a whopping .235 Isolated Power. The 28 year-old crushes fastballs (+0.91 runs above average per 100 pitches seen), curveballs (+1.74) and sliders (+0.79). All of the projection systems expect him to keep finding the gaps and the bleachers often this season:

CHONE: .362 wOBA
ZiPS: .367 wOBA
Oliver: .373 wOBA

From an offensive standpoint, there’s no contest: Napoli is way, way better. While that much is clear cut, measuring the defensive contributions of the two is more difficult. Because of the interdependence of battery mates, it can be difficult to discern a catcher’s responsibility for things like stolen bases, caught stealings, passed balls and wild pitches.

According to Baseball-Reference catcher data (which uses Sean Smith‘s Total Zone), Mathis has been -1.2 runs below average per 135 defensive games. For 2010 CHONE and Total Zone have Mathis as exactly average. Oliver considers Mathis to be about a +5 run defender in a similar amount of playing time.

Napoli has been -7.6 runs below average per 135 defensive games at the big league level. CHONE forecasts -5 run defense in a similar amount of squatting. For 2010, Oliver dings Napoli about 8 runs for his defense.

Let’s call Mathis a .277 wOBA hitter (the average of his three projections), and Napoli a .367 wOBA batter. On a per-plate appearance level, Mathis is about -.0465 runs worse than the average hitter. Napoli is about +0.32 runs better than the average hitter per PA. During their course of their respective careers, Mathis has received 3.25 plate appearances per game, while Napoli has gotten 3.5 per game.

Behind the plate, let’s take the average on Mathis’ two defensive projections, +2.5 runs per 135 defensive games. Napoli rates as a -6.5 run defender per 135 defensive games.

With these numbers in hand, we can get a feel for the number of runs that the Angels will get from the catcher’s spot, depending upon how Scioscia divides the playing time of Mathis and Napoli:


I don’t claim that this is a be-all, end-all look at LA’s catching situation. But even accounting for Mathis being a pretty good catcher and Napoli costing the Angels some runs, the Grand Canyon-sized divide in offensive skill between the two makes Napoli the far better choice to receive the lion’s share of the playing time.

Print Friendly
 Share on Facebook0Tweet about this on Twitter0Share on Google+0Share on Reddit0Email this to someone
« Previous: And That Happened
Next: A Quick Comparison of UZR and Plus/Minus »


  1. Will said...

    What about effects on pitcher ERAs?  We’ve been hearing recently about how much of an effect Rob Johnson had on Seattle’s pitchers, replacing Kenji Johjima and the “Posada Effect” on AJ Burnett relative to the 3rd Molina.  I think this was a glaring omission from an otherwise good article.

  2. Jonathan Sher said...


    Thanks for posting the RAvg for each catcher. Huzzah is correct that it would be helpful to know how often Napoli and Mathis caught each pitcher and make adjustments if necessary, but I think that is a poor basis for dismissing RAvg entirely and concluding that Scioscia is wrong.

  3. Huzzah said...

    I’m not so sure what the RAvg with each catcher behind the plate really tells us by itself.  Perhaps Mathis caught most of Lackey and Weaver’s games whereas Napoli caught the crappier pitchers.  I think it would be a lot better to have some breakdown of how many times each catcher caught each pitcher to get a better idea of how RAvg might be skewed.

    So I still think the analysis in the article is adequate enough to conclude that Scioscia is making a mistake here.

  4. Joe said...

    Good stuff, and I agree.  But I still think the defensive side of the ball is too much of an unknown to draw any real conclusion.

  5. Kahuna Tuna said...

    I had the same idea, Will.  Here are the Angels’ pitchers’ RAvg with each catcher since 2007, the season when Mathis and Napoli became the Angels’ primary catching platoon.

    2007 RAvg
    Mathis:  52 G, 4.26 RAvg
    Napoli:  68 G, 4.66 RAvg

    2008 RAvg
    Mathis:  90 G, 4.10 RAvg
    Napoli:  71 G, 4.65 RAvg

    2009 RAvg
    Mathis:  78 G, 4.22 RAvg
    Napoli:  84 G, 5.16 RAvg

  6. Aaron said...

    Napoli’s offense is comparable to V-Mart’s, better in career wOBA, ISO, BB%, and SLG%, although worse in OBP.  Nobody’s suggesting that Varitek should get very many at-bats, why is there no uproar about Napoli?

    Also, the difference between Napoli and Mathis offensively (as measured by wRC+) is about the same as the difference between Pujols and Cantu.  It’s crazy to be playing Mathis so much.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>