A Look at the Top 5 ISO Decliners

As we all know, power is once again down across the league. This season has seen the lowest home runs per game total and ISO since 1993, the lowest SLG since 1992 and is tied with 1995 for the fewest doubles per game. Let’s take a look at the top five decliners in ISO to determine if there is any hope for a rebound in 2012. Given the lower level of offense, I am not suggesting a full rebound, but a context-relative one.

We all knew Adam Dunn would find his name at the top. There has been enough written about his struggles on this site and throughout the Internet. Unfortunately, it doesn’t seem like anyone has an answer other than pure speculation. The appendectomy, league switch, Ozzie Guillen’s wrath, transition to full-time DH, etc, etc are common responses. Dunn will be 32 next year, so not an exceptionally old age that one should normally be scared away after a down season. I cannot offer anything new, but will say that he will surely be an interesting draft choice next year.

Aaron Hill has been another obvious bust this year. If Hill remains with the Diamondbacks next season, Jeff Zimmerman shows us that the park factors would hurt Hill’s output. Of course, this doesn’t mean that he will hit even fewer home runs next year, just that all else equal, he will likely hit more if he was still in Toronto next season. Either way, it shouldn’t make a big difference and the biggest question is if his power could return regardless of the park he calls home. He will be 30 next year, so still an age he should be near his power peak. All of his skill metrics are right in line with past seasons, except for the mysteriously missing power. The good news is he hits a ton of fly balls. So any rebound in HR/FB ratio will really spur his home run total.

The Braves foolishly bought high on Alex Gonzalez while selling low on Yunel Escobar, and Gonzalez has seen his power dip just as expected. Gonzalez’ power has actually been up and down throughout his career and he had posted a nearly identical ISO to his 2010 season as recent as 2008. So maybe it truly is disappointing to see that mark drop all the way to .114 this year. One of the issues is his lower FB% this season, a level he has not seen since FanGraphs has posted batted ball data. His HR/FB ratio is actually right in line with his history. Another problem is a career worst K%. From a HR/AB perspective, I think he should rebound a bit next year, but a .263 wOBA means he may not see full-time at-bats again.

Jayson Werth’s gargantuan contract was ridiculed the minute he signed it, but no one could have predicted this disappointing level of production. Though Citizens Bank Park has been a bit more favorable to right-handed hitters for power output, it is not enough to explain Werth’s decline. Werth strikes out a lot and relied on a mid-40% fly ball rate in the past, or a HR/FB ratio near 20%. That last number has been all over the place throughout his career, so it has been tough to gauge his true talent level. At age 33 next year, I wouldn’t bank on a complete rebound. Clearly, 30+ home runs is in the rear view mirror, and I would expect something in the range of 20-25 bombs in 2012.

This is easily the lowest ISO Vladimir Guerrero has ever posted, but the third straight year it has been below .200, after 11 straight above that mark. Never the biggest walker, he is hacking more than ever before and has posted the highest O-Swing% of his career to lead the league. He is still making contact at typical levels, but obviously it is harder to hit the ball over the fence when it is off the plate. Vlad will be 37 next year and given his plate approach, will make it tough for him to rebound significantly. With no more speed and a batting average that is suddenly just mediocre, he may last until the reserve round in shallow mixed leagues, and deservedly so.