Revisiting Curtis Granderson

Not too long ago, I delved into the numbers has put up this season. His hot start at the time was not a secret, but I wanted to take a closer look at his performance to see if his numbers were sustainable. He was batting .270/.339/.622. His ISO was a mind-blowing .352!

The conclusion was that his power-surge was not going to last because his peripherals were largely unchanged from his 2010 numbers, but the results were different. Typically when results have changed for reasons that can’t be explained, a player is due for a correction. I believe in accountability, so I wanted to re-examine Curtis’ numbers to see what I got right, and what I got wrong from the previous analysis.

After Wednesday’s game, Curtis is batting .263/.337/.570, with an ISO of .307. In fact, he’s mired in a miserable slump. ESPN is reporting that over the last seven days Granderson is batting a miniscule .105. No one should put much stock in average as a statistic, but no matter how you slice it, .105 is bad.

When I wrote my last post analyzing Curtis, I argued specifically that we could expect his average and on base percentage to remain constant, but for his power numbers to come down. I was drawn to his other worldly ISO. It was unsustainable. Given that his AVG and OBP at the time were good but not great, the safe assumption was that Granderson could maintain his rates of getting on base, but see fewer of his hits go for extra bases, that his correction would occur entirely in his power.

Heading into Tuesday’s game, that conclusion wasn’t actually true. Up to that point Curtis was batting .274/.347/.594. His ISO was coming down, as predicted, but it wasn’t coming down the way I predicted. Instead of maintaining his on-base production with less power, up to that point Curtis had actually improved his ability to get on base, while hitting for less power. This was lowering his ISO, but it was also indicating that part of Curtis’ correction would come in his AVG, which actually was correcting upwards, something I’d never considered.

Now that we’re through Wednesday’s game, it looks like the original prediction is holding true, if anything with risk to the downside. Over his 10 plate appearances in the past two games, Curtis is 0-9 with a walk and five strikeouts. When I wrote the original analysis, Granderson’s walk rate was 9.9% and his strike out rate was 25.9%. Heading into Wednesday’s game, his walk rate was unchanged, but his strike out rate was creeping up, at 26.5%. Unsurprisingly, he’s striking out more just as he appears to be in the heart of this vile slump.

The bad news is that the slump may continue. At the moment Curtis’ ISO is .307. While it is down considerably from its apex earlier this season, that figure would still represent a career high, by a considerable margin. Prior to 2011 Granderson posted his highest career ISO of .250 in 2007, a year he hit .302/.361/.552. Given that there remains no obvious explanation for why Curtis should suddenly have so much more power, the safe assumption is that his SLG has further to fall. One can only hope, however, that his ISO continues to come down without any further downward ticks in his AVG and OBP. That, at least, would soften the blow.