Anthony Rendon’s Sneaky Overhaul

When you think of Anthony Rendon, you probably think of consistency. He’s good every year, in roughly similar ways: he doesn’t strike out much, walks a good deal, hits his fair share of homers and doubles, and plays good defense. He’s been worth more than 4 WAR in every one of his full seasons. He’s a line drive hitter, a batting average machine. If anything, he’s become more consistent over time: in each of the last three years, he’s been worth between 6 and 7 WAR and struck out between 13% and 14% of the time.

I don’t buy it, though. Rendon might seem consistent on the surface, but under the hood, he’s completely revamped his game to unlock progressively more offensive potential. In fact, I can retell the Anthony Rendon story as a progressive improvement over time. Let’s try that now.

In 2015, the first year for which we have Statcast data, Rendon was hurt. He sprained his MCL in spring training, sprained his oblique while rehabbing the MCL, and somehow got forced off of third base — a year after a 6 WAR season — by Yunel Escobar. He played the majority of the season at second and scuffled.

That’s a low baseline, which makes any tale of improvement easier to tell. But let’s start there anyway. Rendon didn’t hit the ball with much authority that year — oblique strains aren’t good for power. When he put the ball in play, he generated a .343 wOBA, significantly below the league average of .361. Those numbers don’t really mean much out of context, so think of it this way: in 2019, Luis Arraez and Kolten Wong were below league average by roughly that amount.

Even in 2016, with no nagging injuries, he was only slightly better than average — think 2019 Michael Brantley. But since then, he’s taken off:

That’s a striking pattern, one I’ve noticed before. But it’s merely an output, and it’s hard to tell a story with only an output. I want to know what Rendon has done to achieve that extra pop.

When I wrote about a new way of thinking about Sweet Spot% yesterday, I found part of my answer. Rendon ranked among the best hitters in baseball at hitting the ball at just the right angle, whether he crushed the ball or made slightly worse contact. That’s not surprising in itself, because Rendon is a great hitter, but it didn’t really track with how I saw his swing in my mind. So I went back and calculated his True Sweet Spot% for every year since 2015:

The reason I didn’t picture Rendon launching his hard-hit balls skyward and spraying medium-hit line drives all over the field is because I was picturing 2014-2016 Rendon, a more grounder-oriented version. But even in the last three years, as his groundball rates have stabilized, he’s continued to make better and better contact. His 2019 featured an additional 7% of batted balls hit in the sweet spot as compared to 2017 despite a groundball rate less than 1% lower.

To explain how this works, we need to look at what he’s done with his hard contact. Take a look at the frequency of each 5-degree bucket of launch angle on his hard-hit balls in 2015:

Some grounders, some screaming, 10-degree line drives, and precious little in the party zone for home runs. We’ve already decided 2015 might be an outlier, though, so let’s look at 2016:

Getting better, though the peak of the distribution is still in the 10-20 degree area, the line drive single or double zone. Let’s look at a time lapse of 2015 to the present:

The center of his hitting profile keeps creeping higher. When he made his best contact with the ball in 2019, he hit the ball between 5 and 35 degrees 75% of the time, roughly the same as 2016. But he hit nearly 45% of his hard-hit balls in the peak home run area, up from roughly 36% in 2016 and 2017.

At the same time, the number of hard-hit balls he “wasted” went way down. Take a look at the percentage of balls hit above 40 degrees or below 0 degrees, basically the only ways you can squander hard contact:

How is he doing this? Partially, he’s pulling more of his hard contact. His pull rate on 95-plus mph exit velocity batted balls has gone up every year:

In other words, when Rendon makes his best contact with the ball, he’s more frequently doing so by getting out in front and driving the ball to left field. There’s some evidence that hitting the ball “early,” further in front of the plate, leads to higher-angled balls in play, and when you’re hitting the ball hard, a pulled ball in the air is exactly what you want.

It makes sense that this transformation would come with a cost. Change your swing to put the ball in the air, and your poorly-hit balls are headed towards outfielders’ gloves at a leisurely pace. But this is an article about Rendon getting better at everything, and of course, he’s increased the percentage of balls hit below 95 mph that he hits for a line drive:

Want it in graphical form? Here’s 2015:

That distinctive horn-shaped pattern is the norm across baseball. Tons of softly-hit balls are mishits, smacked straight down or straight up. The zones you want to avoid here are below 0 degrees and above 35 degrees, and a full 72% of Rendon’s soft contact fell in those zones in 2015.

Over time, the shape of his contact has changed:

The right horn is now bigger than the left horn, which makes sense given that he’s getting the ball in the air a lot more when he hits it the way he wants to. But the percentage of hits that fall in the dead zone has actually declined:

It’s reductive to say that all balls hit either into the ground or into the air are the same. Popups are a worse outcome than softly hit grounders that bounce close to the plate, even if they’re both bad. But even with the increase in popups, his production (and expected production) on soft contact has been basically stable:

This story sounds pretty great. Rendon has improved the distribution of his hard contact, getting it in the air to his pull side more often. He’s done so without sacrificing anything on the rest of his balls in play; he’s swapped grounders for popups but added line drives and flares in the process. Oh yeah, and he’s hitting the ball hard more often:

How has he done all of this? Some of it is because he’s Anthony Rendon. He’s a great talent, a top 10 draft pick with a preternatural work ethic who is realizing his best outcome. But he’s also getting to these better results on contact with some work before he swings.

Want to hit the ball with more authority? Swing at pitches in the heart of the strike zone! Rendon hasn’t always done this, but he’s gone from worse than average to better than average since 2017:

In the meantime, you don’t want to swing in the chase region, naturally. That’s where you chase pitches. Rendon isn’t quite the same passive guy he was in 2015, but he hasn’t gotten that much worse:

He’s swung a little more at pitches in the “shadow” zone around the edges of the plate, but he’s making that work by doing it on his terms. He’s whiffing less often and doing more damage when he connects, a lovely combination:

Some of that is, again, down to him just being better at making contact. But some of it also comes down to when he’s swinging. With two strikes, his shadow zone swing rate has actually declined, not increased. Those are the swings that punish hitters; defensive bail-out hacks that often result in whiffs and soft contact. He’s swinging there on his own terms, when he wants to, rather than getting fooled and swinging there because he has to.

There’s some chicken-and-egg going on here. Is he hitting the ball harder because he’s gotten better at finding the right pitches to hit? Is he getting into situations where he sees better pitches only because pitchers are staying away from him? It’s probably a little bit of both.

Whatever the reason, though, Rendon is a new man. He’s a home run hitter not because of his extreme power (his maximum exit velocity in 2019 was 107.7mph, hardly otherworldly), but because he so consistently gives himself a chance. Per my xHR% formula, he had the 124th-best expected home run rate on balls hit in the air in 2019 — and the 19th-most expected home runs. In other words, he’s getting it done with sheer volume of well-hit balls in the air.

Rendon will be wearing a different jersey this season. But it’s still red and white, and your brain might peg him as the same guy as always, in a new environment but otherwise preserved in amber. It’s not true, though: Rendon hardly resembles his old self when he puts the ball in play. He might not talk about it — he’s a taciturn sort — but Rendon has been a quiet victory for the “launch angle revolution.” He’s elevating and celebrating, and he’s doing it without hurting himself anywhere else in his game.