Giancarlo Stanton’s struggles against sliders won’t last

Giancarlo Stanton has been having a weird season, which has been well-documented. It seems like every time I open his page on FanGraphs or Baseball Reference I come across something new. Today, the revelation was that he has been hitting very poorly against sliders. You could have likely come to this same conclusion just by watching most Yankees games this season, but the numbers really do help tell the story.

Stanton wasn’t always helpless against sliders. In fact, this is the first season since 2014 in which he has posted a negative pitch value against sliders. In recent years, he’s been average or slightly better against sliders overall.

Here’s a graph of Stanton’s wOBA against sliders and cutters over the course of his career:

So what’s different about 2018 that’s causing this poor performance? It could be that he’s seeing more sliders. So far in 2018 Stanton has seen about 6% more sliders and cutters, in favor of fewer fastballs. That might not be the primary reason, though, as his 2018 pitch% numbers are not far off from his career averages.

Stanton has seen a slider or a cutter 28.7% of the time in 2018, only 3% more than his career average of 25.7%. Since Stanton sees 4.11 pitches P/PA, that’s just one extra slider/cutter per every eight plate appearances or so.

Some might be quick to blame his closed stance, or his more aggressive approach. The inconvenient truth is that he used the same closed stance last season in Miami when he hit 59 home runs, and while his swing rate is up slightly from last season, it’s right in line with his career average.

It’s more likely that Stanton’s poor performance on sliders so far in 2018 is due to some bad luck, and a small sample size. If the season ended today, it would be the worst of Stanton’s career against sliders. It’s very likely that Stanton will regress back to the mean, as David Cone enjoys saying.

There’s also his batted ball data to consider, Stanton’s average exit velocity so far on sliders is 92.9 mph. To give that some context, it is noticeably lower than how well he hits fastballs and changeups (96.8 and 98.0 respectively), but it’s right in line with his average exit velocity against all pitches (93.4 mph) which is in the top 3% of hitters in MLB. It’s also actually 0.7 mph harder than he hit sliders all of last season.

Stanton’s hitting sliders just as well as he did during his MVP 2017, but the results are clearly not there. He’s hitting .157 on sliders so far in 2018 compared to .241 last year. Here’s where the small sample size and luck comes in: if six batted balls had found holes (about once every two weeks) his numbers against sliders would be identical to last season.

I know it’s hard to watch Stanton swing and miss at sliders low and away time and again, but things aren’t as bad as they seem. We’ve made it this far, and in all likelihood, there are sunny days on the horizon for Giancarlo Stanton.