Hey! Ian Happ Is Walkin’ Here!

The Chicago Cubs are white hot. Shortly after the All-Star break, the Cubbies were as many as 8 1/2 games out of first place in the NL Central and six games under .500. About three weeks later, they’re a little better than an even-money bet to grab a playoff spot.

So let’s talk about Ian Happ, who has been a key offensive player for the Cubs over that span, and the odd season he’s having. If you make a habit of checking the major league walk rate leaderboards regularly, as I’m sure we all do, you will no doubt have noticed that Happ is in the top five with a 16.1% walk rate. (All stats current through Tuesday’s action.)

Now, Happ has always been capable of drawing a walk; his career walk rate heading into this season was 11.2%, which is pretty high. But you wouldn’t think of him as one of the most discerning hitters in baseball — Juan Soto, Kyle Schwarber, Max Muncy, and so on. Until this season.

If you drop the minimum plate appearance threshold to 300 PA, Ryan Noda pops up with the second-highest walk rate in baseball, which is of interest (though perhaps only to me) because Happ and Noda played college baseball together. It’s pretty common for college teammates to succeed together in the pros, but Happ and Noda attended the University of Cincinnati, which is far from a baseball powerhouse. The Bearcats mostly exist to hand one extremely annoying loss per season to either Louisville or a Big Ten team.

Only six Bearcat position players have appeared in the major leagues since the introduction of the Wild Card: Happ, Noda, Kevin Youkilis, Josh Harrison, Tony Campana, and Joey Wiemer. Which means Weimer is eventually going to have to choose between becoming an on-base machine or a nightmare to tag out in a rundown.

And he will have time to choose, because Happ wasn’t born this way.

The question with Happ, as it is with all switch hitters, is whether to treat him as a single unified hitter, or to take an approach informed by the Kurlans from Star Trek: The Next Generation. In short: Is he one hitter, or two?

Happ has walked this much from one side of the plate in previous individual seasons, but never both at the same time. Taken on the whole, Happ is absolutely swinging less, and walking a lot more, than he did last year. In fact, no hitter has improved his walk rate as much as Happ has from last year to this one:

The change in Happ’s game is pretty easy to spot. Here’s Happ’s Swing% heat map as a left-handed hitter against righties in 2023:

That heat map shows, to me, an outstanding sense of where the zone is and where it isn’t. Happ goes after pitches out over the plate, especially up in the zone. No wonder he’s walked 16.9% of the time from the left side this year. That’s up almost six percentage points from his left-side walk rate in 2022, but the shape of the heat map is similar.

Now, contrast that to his right-on-left heat map from 2022:

This is a mess. If the ball is middle-in and anywhere near the zone vertically, Happ is going after it. Last year, he walked just 5.0% of the time in his right-handed plate appearances, his lowest mark from either side of the plate since his rookie year. This year, he’s cleaned that up a lot:

He’ll still chase up and out of the zone, but he’s laying off pitches low and in. As a result, his walk rate from the right side is up to 14.0%.

You can see Happ’s newfound selectivity here, with his swing rate and wOBA by attack zone. The shadow and chase zones are where hitters get themselves into trouble, and Happ has become much more selective in these fringe areas:

I’m convinced that Happ has taken a huge step forward since last year in terms of strike zone judgment. He’s making fewer bad decisions around the edges of the zone, and drawing tons more walks as a result. Like, it’s hard to overstate the effect of a seven-point jump in walk rate for a player who was already a good hitter to begin with.

So why is his wRC+ basically the same as it was last year?

Already in this chart you can see one of the two possible explanations: Happ is getting screwed on batted ball luck. Or at least, he was getting absurdly lucky last year and has regressed to the mean. I’d buy that explanation, particularly because he’s hitting slightly more line drives and fly balls this year than he did in 2022. But I already spent a bunch of time poring over Happ’s approach and production by batting side and attack zone, so why not look a little deeper?

Let’s look at a third attack zone: the heart of the plate. This is the zone where you’d expect hitters to have the highest swing rate, because anything they take is all but certain to be called a strike. It’s also where you’d expect hitters to have the best offensive numbers when they do swing, because if a pitch is in the heart of the zone, you want to hit the bejeezus out of it:

That’s a little concerning. Happ’s swinging less here, too, in the region where you want to swing as much as possible. But maybe he’s not being passive, just merely more selective, and he’s getting more bang per swing on fewer swings over the middle of the plate:

Thank you for bearing with me through all this Statcast jargon, by the way. I’m well aware that Heart Contact Quality sounds like a special Dashboard Confessional LP where Chris Carrabba re-records all the band’s fully electrified singles like “Stolen” and “Belle of the Boulevard” in the stripped-down solo acoustic guitar style circa The Swiss Army Romance.

Anyway. Happ’s (relative) lack of power on pitches in the heart of the zone would jive with the 30-point drop in SLG that’s accompanied his 30-point rise in OBP from 2022 to 2023. His hard-hit rate is down this year as well. The discrepancy between Happ’s wOBA and xwOBA seems to point to an impending power resurgence, but I’ll throw one last table at you that suggests that Happ has actually lost a smidgen of power since last season:

If Happ has decided to trade power for OBP, I think it’s a smart trade. Happ is 20th out of 144 qualified hitters in OBP this year. Last year, he was 55th out of 130 in SLG. Simply put, his ability to get on base now is rarer than his power was in 2022. Alternatively, he’s shored up a huge weakness in his plate discipline, and is a couple cans of spinach from making better contact on pipe shots and turning into the second coming of Chipper Jones. Either way, walking more is good for you. We’d all lead healthier lives if we did the same.