Reynaldo López, Looking Up

Reynaldo López had a bummer of a 2019. Offense is high around the league, but a 5.38 ERA is still terrible. Pitchers don’t adjust for league offense or batted ball luck in their heads; they pretty much know the way the numbers work. Two is otherworldly, three is good, four is average, and five is “what am I doing wrong?” Honestly, it doesn’t even get that much better if you do get fancy; he had a 5.04 FIP and a 5.27 xFIP, so it’s not as though he was just getting unlucky. Those were 8% and 15% worse than league average, respectively — not great.

But wait — López was worth 2.3 WAR last year. That’s not Jacob deGrom or anything, but it’s a totally acceptable number, not at all in line with the string of fives that comprise his runs allowed statistics. Is this just a sign of how bad replacement level pitchers are? Nope! It’s a sign of a quirk in our WAR calculations and a quirk in López’s game.

When we calculate a starting pitcher’s WAR, we use FIP, with one small modification. Infield fly balls are automatic outs, and in our WAR calculations (but not in the FIP numbers we display) we count them as such by treating them as strikeouts. It’s a true enough outcome — infield fly balls pretty much always turn into outs. Grounders, line drives, and other fly balls are all soup, but a popup’s fate is known the moment it’s launched.

López gets a lot of infield fly balls. In 2019, he led the majors with 36. In 2018, another year where he managed 2.3 WAR with a 108 FIP-, he tied Max Scherzer for the major league lead with 38. Outs don’t get much easier than this:

Even disregarding the excellent throwbacks, that’s an aesthetically pleasing video. The backup slider gets Goodrum reaching, the entire infield ends up around the mound, and I love López’s half-hearted flash of leather before he turns and vacates the scene.

“But Ben,” you might say. “López was still bad despite those popups. Why is this interesting?” Well, his run prevention numbers weren’t great in 2019, no disagreement from me here. But “he was bad, why is this interesting?” used to be something people said about FIP, before we had years of familiarity with the statistic to show our lizard brains that it really does tell you more about a pitcher’s skill level than ERA. Why not popups?

Before I get into that and confess my own confusion around popups, it’s time for another GIF break:

Oof — that has to sting. Up and in like that, Devers had no shot after he committed to swing. He knew it right away:

Back to the data! Raw infield fly ball totals are one thing, but rate stats matter too. If López is just getting all of these easy outs because he’s an extreme fly ball pitcher, maybe he’s less interesting by a little bit. And to be clear, he is an extreme fly ball pitcher. In 2019, he had the lowest GB/FB ratio in baseball. In 2018, he had the fourth-lowest. He’s not Zack Britton out there, not by a long shot.

Even after adjusting for the high clip at which batters put the ball in the air, though, López stands out. In 2018, he had the fourth-highest IFFB%, the percentage of fly balls that didn’t leave the infield. In 2019, he had the third-highest IFFB%. At his high fly ball clip, turning 4.6% of fly balls (the gap between his rate and league average) is no joke.

López allowed 250 fly balls, which means 11.5 extra popups. If we displayed a pFIP that added pop flies to strikeouts, the boost from moving to López levels of IFFB’s from league average levels would be worth 0.13 runs of FIP, a not-insignificant change. Even if you buy the conclusion of my batted ball research earlier this year and regress his results toward the mean, there’s still value here. Being such an extreme outlier has its merits.

Does this feel like a lot of math? It does to me! Time for another GIF break:

Top of the zone cheese, uncomfortable swing: looks like an easy out to me.

Sometimes in a FanGraphs article, this is the pivot point. The first half was about some dude you’ve heard of who did some weird thing you didn’t know, and then BAM, the second half of the article uses that as a jumping off point to explain a hidden truth about baseball. This is emphatically not one of those articles.

You see, if you wanted that, you could just read Alex Chamberlain. He finished an exhaustive look into exactly what you think this article will be about last week, and it’s well worth your time to read it if you’ve always suspected that pitchers have control over whether opposing batters mishit the ball.

There’s a table at the end of that article, and if you don’t have the time to dig through it, I’ll save you the suspense: López isn’t good at avoiding the money launch angles for hitters. He’s one of the worst in baseball at it, in fact. He might get a bushelful of popups, but he also spends his fair share of time shaking his head in disbelief as a baseball crashes off of something ludicrously far away.

That’s not to say he’s hopeless. Alex focused on a few bright-line groups — 18 to 22 degrees, 12 to 27 degrees, and eight to 32 degrees. Those track roughly with the highest batted ball values for hitters. If you instead focus on the batted balls where pitchers decisively win, balls that they get batters to hit either below zero degrees or above 50 degrees, López is better than average. He gets the completely free outs, the grounders smashed into the dirt or lazy fly balls, quite well. The rub is in the rest of his pitching.

Does this matter for our understanding of Reynaldo López? I think so, if only a little. Steamer projects him to have an ERA 0.13 lower than his FIP this year. ZiPS has them about even, but likes his overall production more. Both systems think he’ll be a useful contributor for the White Sox in 2020. The popups are a key reason why that’s the case, despite the home runs and loud contact — and boy, does he allow his fair share of home runs and loud contact.

That doesn’t mean we’ve cracked the case, or that we can just toss away our work and stop researching. There’s more to understand about what pitchers can and can’t do to stymie batters — I’ll save this for another day, but I think there’s something to looking at launch angle standard deviation. But it does mean that my work here is done. López gets a bunch of popups, and that isn’t likely to change.

Let me leave you with one last great frustration, though. When I first titled this article, it was called “Reynaldo López, Pointing Up.” I love that classic pitcher celebration, the emphatic point skyward that infielders most certainly don’t need. Oh, the ball’s up there? Thanks, guy! It’s not to help infielders, but rather an acceptable way to celebrate how thoroughly you crushed the batter’s hopes and dreams. But watch another one, from the perfect angle to see his reaction:

Now, I’m not actually sure if that ball went into our system as an infield fly ball, but it was a sure out nonetheless. And there was López, stone-armed, spinning around to watch his masterpiece. He’s not a pointer-upper, despite ample opportunity to do so. So let me be the first, and maybe only, baseball analyst to say: more popup celebrations, please, Reynaldo.