Hitter ISO Surgers

Yesterday I discussed the five hitters whose isolated slugging percentage (ISO) has declined the most compared with last year. So today, of course, I’ll check in on the hitters who have enjoyed a surge. Unfortunately, it comes without a super clever title. But, I promise you the analysis remains top notch :-). And yes, that may have been the first smiley ever inserted into a FanGraphs article. I try to start trends, what can I say. I limited my comparisons to those hitters who are “qualified” this year and also accumulated 400 plate appearances last year.

Name 2013 ISO 2012 ISO 2013 HR/FB 2012 HR/FB ISO Diff
Chris Davis 0.375 0.231 32.6% 25.2% 0.144
Carlos Gonzalez 0.289 0.207 23.9% 18.8% 0.082
Justin Upton 0.217 0.150 19.4% 11.0% 0.067
Jason Kipnis 0.183 0.122 14.3% 9.7% 0.061
Brandon Belt 0.203 0.146 11.4% 6.2% 0.057

Well obviously mister Davis, now affectionately called Crush, sits atop the list, and it isn’t very close either. He has gained about 13 feet of batted ball distance, which is not enormous, but certainly meaningful. But aside from the added muscle behind his fly balls and home runs, the following table is also interesting:

Season Pull Center Opposite
2012 43% 29% 28%
2013 49% 29% 23%

That is a rather significant increase in the percentage of balls he has pulled this year. It requires much more strength to hit a ball out to the opposite field (which Davis does possess), so an increased pull percentage could be another piece to the Chris Davis 2013 story. Whether the change in the location of his batted balls is a conscious decision and sustainable, I don’t know. But it does help explain his performance this year. Unfortunately, the improved strikeout percentage we saw earlier in the year couldn’t be maintained and even with the higher pull percentage, you just cannot project a 30%+ HR/FB rate again. So he’ll probably be overvalued in drafts next year.

Carlos Gonzalez is second in baseball in home run plus fly ball distance, behind who else, Miguel Cabrera of course. Gonzalez was second last year as well, but he has gained two feet this season, which is fairly insignificant. His HR/FB rate remains at a reasonable level, so the primary reason for his power surge is a career high fly ball rate. CarGo never really hit as many fly balls as you normally would expect from a power hitter and that has changed this year. This could be a conscious decision as it usually requires a change in swing plane. We won’t know until next year if the FB% spike will be repeated, but that will go a long way into determining how close he comes to his current AB/HR rate.

Back in late February, I nabbed Justin Upton as a power rebound candidate. After performing an exhaustive study using ESPN Home Run Tracker data, Upton appeared at or near the top of both lists I compiled that suggested better times were ahead. Whether it was injury related, bad luck or a little of both, Upton was clearly better than a mere .150 ISO and 11% HR/FB rate. Interestingly, his batted ball distance has only increased by a couple of feet this year, but a lot more balls are flying out. In fact, his HR/FB rate is at a career best at the moment. Of course, a decline in steals means that his fantasy value isn’t actually any higher than it was last year. And with the entire Braves roster running less frequently, it’s not something you can count on returning next season.

Jason Kipnis appears here mainly because of how disappointing he was from a power perspective last season. He routinely posted ISO rates near .200 in the minors and knocked 7 homers in just 136 at-bats during his cup of coffee with the Indians back in 2011. So I’m not sure which was more of a surprise, the 14 homers he ended up hitting in 2012 with just a .122 ISO or the 31 bases he swiped. This year he has decided to do it all, as he continues to steal bases at a much higher clip than his minor league record suggests he is capable of and his power has jumped back to where many expected it to be last year. His batted ball distance has only increased by about six feet, but he was probably a bit unlucky last year, so this year’s power looks largely legit. I am still not super confident that he will continue to steal 20+ bases a year, but nothing in his statistical profile suggests that he’s any bit a fluke this year.

After posting fantastic ISO rates everywhere he landed, Brandon Belt‘s 2012 performance was quite shocking. Only 7 homers in just over 400 at-bats? Really? He hit more in 2011 in less than half the at-bats! But as one of this spring training’s success stories, he got a bit of cautious sleeper hype. He ranked second in slugging percentage and tied for second in homers during the spring, providing at least some of us optimism that his power might be ready to explode. The good news is that his HR/FB rate still sits at just above 11%, which is low enough to imagine further upside in the future. A fly ball rate above 40% also helps, but he just plays half his games in a terrible park for left-handed home runs. His HR/FB rate this year in away games is more than double his home game mark. AT&T Park sports an 87 home run park factor for lefties, so we can’t really expect his splits to improve. But, his improvement does look sustainable.

Print This Post

Mike Podhorzer produces player projections using his own forecasting system and is the author of the eBook Projecting X: How to Forecast Baseball Player Performance, which teaches you how to project players yourself. His projections helped him win the inaugural 2013 Tout Wars mixed draft league. He also sells beautiful photos through his online gallery, Pod's Pics. Follow Mike on Twitter @MikePodhorzer and contact him via email.

2 Responses to “Hitter ISO Surgers”

You can follow any responses to this entry through the RSS 2.0 feed.
  1. Mario Mendoza says:

    Funny, I remember seeing a lot of PacBell “splash downs” on TV as a kid.

    If Belt ever gets the SLG up, he will be great. But what’s funny is how sneaky-good his OPS has been the last two years, relative to the depressingly pathetic NL 1B field.

    Vote -1 Vote +1