Visualizing Paul Goldschmidt’s Slump

Let’s face it, Paul Goldschmidt hasn’t been going so well lately. I mean, he’s still been good, but good isn’t great and great is what we’re accustomed to seeing out of Goldy. He’s an MVP-caliber player who’s been playing like a solid regular for the last month. Guys like David Peralta, Welington Castillo and A.J. Pollock have been picking up the slack, but there’s no confusing that this is a Goldschmidt-led team. So we have to wonder, what the hell is going on?

The answer, it seems, is convoluted. After watching him at the plate over the last couple of weeks and subsequently pouring over the data, there’s no “one thing” that stands out. Well, maybe there’s an explanation, but we’ll get to that later. The drop off is clear, however. From the start of the season through July 9th, Goldschmidt was slashing .349/.466/.618. Since then, he’s hitting a much more pedestrian .295/.394/.432. The average is down, but no one’s going to complain about a guy hitting almost .300 and getting on base nearly 40% of the time. The massive drop is in the power department where Goldschmidt’s ISO has fallen from .270 to .136. Something’s up, but again, finding the culprit isn’t necessarily easy.

For now, let’s look at several components of Goldschmidt’s production over the season. To start with, let’s look at the overall production via wOBA (click to enlarge).

Goldy’s start was excellent and he maintained the progress through the first three full month of the season. Where a .330 is good, we can see that Goldschmidt was routinely well above this number during most games through June and into July. In fact, there are several monster games where he posted a w/OBA above .800. But that production dropped off steeply right around the all star break. He’s still posting good numbers, but they aren’t anywhere near the levels that we’d seen previously. He’s walking a ton and still notching hits, but the decrease in power is driving his game-by-game w/OBA down.

Maybe there’s something in how he’s hitting the ball that’s dragging him down. Let’s look at his ground ball, line drive and fly ball rates over the season (click to enlarge).

 Here it appears that, in the last month, he’s traded in some fly balls (yellow) for line drives (blue) and grounders (green). The line drives and grounders are nice for racking up hits, but without the fly balls we’re not seeing the homers and long doubles. Sure, fly balls turn into outs more often than any other type of batted ball, but they’re also where the power production comes from.

Is he hitting the ball less hard en route to this drop in fly balls? I’m glad you asked. Here are his hit types by velocity over the season (click to enlarge):

There is a decrease in hard-hit balls over this span, too. A few more soft hit balls can be found and he’s still notching plenty of medium hit balls, but the hard hit stuff seems to have dropped slightly. This would suggest that he’s not making quite the same level of contact as he was previously. Since Goldy does so much damage by punishing baseballs it’s no surprise that the outcome would change if he were hitting it differently.

Of course, that might not be of his doing. Are pitchers giving him less to hit these days? After all, you couldn’t really blame them for feeling victimized for the first three months of the season. Here is the rate of pitches in the strike zone that he’s seen over the course of 2015 (click to enlarge).

Well, that doesn’t appear to be the culprit. There have been fluctuations all year long, but it doesn’t appear that he’s seeing a lot fewer pitches in the zone by any means. In fact, things have trended upwards slightly over the last two weeks or so. It’s not like Goldy isn’t getting pitches to hit, he’s just not doing the same things with them.

And for one final check, we can look at his plate discipline, just to make sure that he’s not pressing and making bad decisions up there. Here are his in-zone and out-of-zone swing rates (click to enlarge):

Again, there’s not much here. There are a few spikes in his out-of-zone rates, but for the most part, things are in line with his early marks in the season. He may be chasing ever so slightly more, but it’s nothing drastic. If anything, he appears to swinging at a few fewer pitches in the zone which might be a better indicator of his current funk than anything. The drop in pitches swung at in the zone might show us that he’s uncomfortable at the dish, at least by his herculean standards.

Putting it all together, we can clearly see the drop in production, but we can’t exactly see why. He’s not being pitched to in a drastically different manner. Paul Goldschmidt can hit any kind of pitch in any part of the strike zone. We know that. He’s still doing that, but he’s doing that with less authority than before.

If I had to venture a guess as to why, I’d suggest something that won’t show up in the graphs: Paul Goldschmidt is tired. He’s playing every day and has been doing so for almost the entire season. He’s played in 109 of the team’s 110 games through Sunday. He may be Arizona’s Superman, but even Superman needs a break every once in a while. He didn’t get it over the all star break like a lot of other players did and he just received his first full day off last week.

There’s a reason for that, of course. They simply can’t afford to take him out of the lineup. When Jarrod Saltalamacchia is the back up first baseman, you know you’ve backed yourself into a corner. There’s no viable alternative on the roster. So while Goldschmidt is struggling, it’s likely he’ll have to power his way through it. Hopefully he can find his comfort at the plate again as Arizona chases as .500 season. If he doesn’t, it’s unlikely they find their way to that mark before 2015 runs out.