MASH Report – SLOWest Bats

During the 2013 season, I created three metrics to help find possible injuries: PAIN, HURT and SLOW. So far this offseason, I have looked back at the final 2013 values for PAIN and HURT. I have put off SLOW ( Swinging Late or Whiffing) because the data was a mess a to query and work with.I finally simplified the process so the following is a look at the 2013 SLOW leaders. Also, I will examine if a SLOW bat was behind the second half struggles of Jason Kipnis and Jean Segura.

I created SLOW to see which hitters struggle with fastballs right in the heart of the strikezone. The two requirements are:

  • Heart of the strike zone (almost 99% of pitches called strikes and damn you CB Bucknor).
  • Fastball speed equal to or greater than 92 mph.

The three items I used to create the metric is:

  • Contact%
  • Foul%
  • Pull%

Enough of the background data, here is the 2013 leader board:

To show how bad the top hitters have contact issues, here is’s fastball description for the highest SLOW value players which saw at least 100 pitches in the plate’s heart

  • B.J. Upton: Against All Fastballs … a disastrously high likelihood to swing and miss
  • Justin Upton: Against All Fastballs … an exceptionally high likelihood to swing and miss.
  • Carlos Gomez: Against All Fastballs … a high likelihood to swing and miss.
  • John Buck: Against All Fastballs … an exceptionally high likelihood to swing and miss
  • J.P. Arencibia: Against All Fastballs … a high likelihood to swing and miss.

B.J. Upton really struggled with fastballs compared to previous seasons. His fastball run values per 100 pitches went from .51 in 2011 to .89 in 2012 to -.47 in 2013. Upton basically went from crushing fastballs to being owned by them. For him to turn it around in 2014, he will need to make contact with a few more fastballs.

Besides season to season comparisons, I ran 1st and 2nd half comparisons which stemmed from this comment by chri521 a few months ago.

I wonder if Segura ever showed up at the cusp the the “SLOW” Mash report list? Might lend credence to his fatigue if his batspeed is waning if he’s dropped well hit % and increased IFFB%?

Just last week, I looked at how Jason Kipnis and Jean Segura both struggled in 2013 season’s second half. To see if their bats slowed down, here is the first half to second half SLOW values  ranked by difference.

Kipnis and Segura both had decent overall SLOW values and little changed between the halves.

Name: 1H SLOW, 2H SLOW
Kipnis: 15.8, 24.5
Segura: 46.4, 40.4

One player at the top of the list who did change quite a bit was Mr. Mike Trout. He went from an 18 SLOW to 62.3 SLOW. Looking at his numbers, he basically went from above average against fastbalsl to below average. But over the course of the season, his overall SLOW values  evened out. In 2012, he had a  SLOW value of 38. In 2013, it was 38. Nothing to worry about, but it is always good to check.

Players always get labeled with a slow bat, but it is tough to tell for sure without watching a couple dozen at bats. I created the SLOW metric to find hitters who have problems catching up with fastballs. For 2014, SLOW can be used to find these slow hitters and then they can be closely examined to see if an injury may be behind the decline.

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Jeff writes for FanGraphs, The Hardball Times and Royals Review, as well as his own website, Baseball Heat Maps with his brother Darrell. In tandem with Bill Petti, he won the 2013 SABR Analytics Research Award for Contemporary Analysis. Follow him on Twitter @jeffwzimmerman.

12 Responses to “MASH Report – SLOWest Bats”

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  1. Nick Norris says:

    Can you differentiate between a slow bat and a batter being surprised by fastballs aka bad approach or situational or count awareness?

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  2. Adrock says:

    Interesting stuff. Would it be possible to edit the pitchers out of the list? That would contribute nicely to readability, as we know most pitchers can’t hit. Thanks!

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  3. shibboleth says:

    Awesome metric, thanks for sharing. I’ll be paying a lot more attention to all 3 of these!

    So Segura is not necessarily nursing an injury, but that only means more skepticism for a repeat of his 1H, yes?

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    • Grant says:

      He was a guy who had played the winter ball in 2011 and 2012. Throw in the minor and major league seasons to that and this is the first offseason he’s had in 3 years. His teammates had hinted at him playing despite being worn out in the second half. It’s a qualitative thing, but it makes sense. I don’t think that he’s a top 5 player in baseball overall like he was in the first half. But I like his chances of being the best SS.

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  4. Mike Harber says:

    Thanks for letting us know that JP Arencibia is not good at hitting baseballs with a bat.

    We were not sure, until just now.

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  5. scottzdiamond says:

    Any way this can be edited to include a top and bottom 10 list? Those charts, while awesome, are incredibly dense.

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  6. Mike Lowe says:

    Jeff, this post is riddled with errors.

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  7. adam says:

    // // \\ \\

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  8. Nope says:

    This is a pretty weak post. Charts are unmanageable and include pitchers which is unneeded info.

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  9. chri521 says:

    Jeff I’m honored to have sparked a thought for an article! SLOW only measures pull, foul (late) vs. contact right? My original though was perhaps layering on more metrics like good vs bad contact (LD vs IFFB) which may be due to overswinging or guessing to compensate for slower speed.

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