This version of Nolan Arenado is even better

Credit: USA Today Sports

Credit: USA Today Sports

This story was originally published on Baseball Prospectus

The third pitch Nolan Arenado saw from Cubs right-hander Kyle Hendricks on June 4 was five or six inches off the plate. Arenado swung and pushed it up the middle for an infield hit on a ball that glanced off Hendricks’ glove. He started his second at-bat of the night by swinging at an up-and-in fastball and fouling it off. In his final two at-bats, he saw a total of three pitches.

Arenado’s approach at the plate that night was an exaggeration of his season. He currently holds his highest overall swing rate since 2016 and highest out-of-zone swing rate since 2013. But among all of this aggression, he’s making an exceptional amount of contact. On June 6, his 15-game rolling average contact rate touched 88 percent, his highest mark since June 2016. His output has been a career-low strikeout rate and projections that suggest he’s on pace for his best season since 2016.

When I asked recently whether he’s conscious of his aggression at the plate, Arenado responded simply, “Yeah, I am.” He ranks fifth among all major-league hitters in WARP this season, behind only Cody BellingerMike TroutAlex Bregman, and Christian Yelich, and he’s on pace to surpass his previous career-high. But while he acknowledges his refined approach, this version of Arenado is one that even he can’t explain.


Arenado’s teammate Mark Reynolds pointed to two factors when asked why a hitter might swing more: how he’s feeling at the plate and his comfort level against a pitcher. The latter doesn’t hold over the 60-game, 250-plate appearance threshold Arenado has crossed. Little evidence suggests that he’s simply facing pitchers against whom he’s more comfortable. The former is subjective, difficult to measure, and a common response to any reportter asking variations of the question “why are you better?”

We can hypothesize that there might be periods of time where hitters are locked in and hit the ball harder, just like research by Rob Arthur and Greg Matthews showed for pitchers, but feeling better and chasing more pitches seem counterintuitive.

“Baseball players are generally just idiots and can’t really explain anything,” Reynolds said with a laugh when asked if any other reasons for aggression came to mind.

Arenado’s swing rate sits in the 87th percentile of qualified hitters this season, his highest mark in any of his last three seasons by an average of four percentage points. “It’s drastic how much your average goes down [with two strikes] and drastic how few pitches you get to hit,” Arenado said. “I’m trying to be the aggressor up there.”

This aggression makes sense for hitters like Arenado who can incrementally increase swing rate and have their contact rate follow. However, players like Arenado are few and far between. He’s one of just 15 qualified hitters to increase both their swing rate and contact rate between 2018 and 2019, and one of only three to increase both by three percentage points or more. For Arenado, this uptick in swing rate is a way to avoid counts where he performs poorly (by his standards).

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While swing rate stabilizes quickly for hitters, Eno Sarris pointed out some factors, like new teams and contracts, that can artificially boost swings beyond the point of stabilization. Arenado did sign a huge contract extension in February, but his approach appears more deliberate. His swings have come early in counts, supporting his statement about falling into two-strike counts. His swing rate has increased seven percentage points in 0-0, 0-1, and 1-0 counts from last year, and pitchers are throwing him a nearly identical mix of pitches.

Fastball location against Arenado in early counts suggests more offerings are creeping up in the strike zone and in on his hands. When Arenado’s teammate, pitcher Jon Gray, was asked why pitches might be leaking back over the plate against a hitter, he cited a hitter’s movement in the box. “That can kind of be tough visually,” Gray said. “Some guys will really move a lot in the box … it just all depends on what your target really is as the pitcher.”

Arenado’s approach doesn’t jibe with Gray’s guess. His setup is relatively quiet and neutral in terms of distance from the plate. But pitchers are still riding in and Arenado is still swinging. Observe his tendency to swing at elevated, early count fastballs, a deviation from 2018 when he centered his hacks in a smaller part of the zone.

All of Arenado’s swings at fastballs in 0-0, 0-1, 1-0 counts; Credit: Baseball Savant

All of Arenado’s swings at fastballs in 0-0, 0-1, 1-0 counts; Credit: Baseball Savant

“I’m able to recognize what’s a ball and what’s a strike right now and I think that’s really helping me,” Arenado said about why he’s swinging at these pitches creeping up and in. As the 2019 heatmap above shows, there are varying levels of truth to his claim. He is swinging at fastballs up in the zone at a higher rate, but the shades of red beyond the zone are pitches he’s chasing, which supports his increase in swings on pitches out of the zone.

Arenado told me he feels like he can do more damage on pitches in on his hands and that he struggled to capitalize on those pitches last year. The data shows varying levels of truth to that statement as well. This season he’s produced the least amount of value on pitches on the inner third compared to any of his prior three seasons. For comparison, last season he slugged nearly 270 points higher on these pitches. As Reynolds says, sometimes hitters simply can’t explain things they’re doing. Arenado’s aggression has some logic to it, but other elements are a mystery.

In the endless chess match of pitcher versus hitter, Arenado’s move this season has been to loosen up and swing more, particularly on fastballs up and in. A product of his aggression has been the highest DRC+ of his career (142) and a 12 percent strikeout rate compared to 18 percent last season. The next move is for pitchers to counter. “I would try to throw a breaking ball, put something else in his mind, and if I know he’s sitting dead-red heater, I’m going to go changeup,” Gray said in response to how to attack a hitter swinging more at elevated fastballs.

Given Arenado’s aggression in 2019, more breaking balls might be the correct move for opposing pitchers. His percentage of fastballs seen is down over three percentage points this season compared to 2018, but he’s still right around the league average. In typical Arenado fashion, however, he’s hitting sliders better than he has since 2016.

In fact, based on performance against a variety of pitches in different parts of the zone, Arenado has little in the way of a hole in his swing. Breaking balls down and away are what he swings and misses at most, but his overall performance against them is still above average. He’s counter-punched the league and even if it subsides with time, this phase showcases how an elite hitter like Arenado can manipulate his approach and evolve beyond career norms.