The Astros Are Down with OBP

After Jose Altuve scorched the Brewers for four hits in five plate appearances yesterday, I did a little research. I have been following his major league career a tiny bit, as I own him on a fantasy team. I picked him up after Kevin Goldstein’s obsession with him last season. Basically, he’s a little guy that can hit but lacks any sort of plate discipline. In fact, that’s exactly what happened last year. In 234 PAs, he had a .276 batting average (not bad for a 21-year old) and a 2.1% walk rate. However, this year in 77 PAs, his walk rate is an above-average 9.1%. Derek Carty found that walk rate stabilizes after 168 non-IBB/HBP PAs, so the sample size is not yet large enough, but it is about halfway there.

Obviously, this realization required a deeper look. That very day, Astros beat writer Brian McTaggart noticed that while the Astros batting average and slugging percentage through 19 games are very similar to last year, their on-base percentage is 20 points higher. Astros front-office analyst Mike Fast replied to that post with “Interesting comparisons. I love seeing that OBP where it is this year so far.” Of course you do, Mike.

So what is leading to the Astros increased on-base percentage and is it a result of the new Jeff Luhnow-run front office? Well I can’t answer that second question because I’m not on the inside, but I may have some input into the first. I do believe that there is a systematic change in the Astros hitters’ approaches this season.

The first difficulty in looking at this is that so many of the Astros hitters are fairly young, so they don’t have a good amount of MLB PAs to compare this season with. However, since walk rate does stabilize so quickly, the numbers should still be helpful. I compared each player’s 2012 plate discipline numbers with their 2011 ones. Jason Castro and Justin Maxwell did not play in 2011, so I used their 2010 numbers instead.

I found the top 12 hitters in PAs for the Astros this season, excluding rookie Marwin Gonzalez. Then I compared their BB%, O-Swing%, Z-Swing%, Swing%, O-Contact%, Z-Contact% and Contact%. between 2011 and 2012. You can read about the definitions of these stats on Fangraphs (their custom leaderboards and player lists made this very easy). I used the pitch-fx versions of each of them.

This is what I found. Positive numbers mean the number is higher in 2012 than it was in 2011. (I apologize for the poor formatting)

Name 2012 PA BB% Percent Swings Out of Zone Percent Swing In Zone Percentage of Pitches swung at Percentage of contact outside zone when swinging Percent contanct when swinging in zone Percent contact when swinging
J.D. Martinez 81 11.50% -9.30% -10.90% -10.30% -0.90% 5.70% 4.60%
Jed Lowrie 57 7.30% -4.30% 1.90% -2.30% -4.30% -5.40% -4.60%
Jose Altuve 77 7.00% -16.30% -16.30% -16.60% 16.80% 0.10% 6.50%
Brian Bogusevic 70 4.70% -12.30% -6.50% -10.10% 3.90% 9.40% 9.60%
Jordan Schafer 84 3.60% -4.60% -8.00% -5.90% -9.70% -10.50% -9.90%
Carlos Lee 86 1.50% -0.90% -2.60% -2.50% 0.20% -0.60% -0.70%
Jason Castro 47 0.50% -4.00% -0.80% -1.40% 2.90% -2.30% -0.10%
Travis Buck 25 -1.00% 2.40% 7.00% 2.50% -10.90% -2.80% -7.10%
Matt Downs 18 -2.10% 7.50% -1.60% 1.50% -3.10% 2.10% -3.40%
Chris Johnson 75 -2.70% 0.90% 1.20% 0.70% -11.10% 2.10% -3.00%
Chris Snyder 33 -5.20% -0.60% 3.90% 1.40% -35.70% -13.10% -18.00%
Justin Maxwell 21 -14.30% 0.60% 1.40% 3.60% 10.90% -7.80% -0.70%

Martinez, Lowrie, Altuve, Bogusevic, Schafer and Lee have all improved on their walk rate so far this year. Johnson is the player with the most PAs this season who is walking less. Maxwell’s walk rate is severely down, but he only has 21 PAs. Of those six players who improved on their walk rate, all of them are swinging less overall and out of the zone and all but Jed Lowrie are swinging less in the zone. Interestingly enough, only Martinez, Altuve and Bogusevic have seemed to improve their contact rates overall. Lowrie and Schafer are actually making much less contact when they swing.

Six of the top seven Astros in PAs this year have increased their walk rate by swinging less. This has led to their increase in OBP. I imagine Manager Brad Mills walking into the clubhouse at the beginning of the season and saying, “Gentlemen, this year you’re going to stop swinging at borderline pitches you can’t hit. If you see a pitch coming and you can’t do anything with it, let it go.” Then a lightbulb pops up over their heads and they say, “Oh! I get it now!” And then they pop a Naughty By Nature tape into the boombox and start to dance.


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