July 6, 2022

Statistically Speaking: Anthony Rendon’s Swing

Sitting atop the Washington Nationals leaderboard in several offensive categories, Anthony Rendon is having himself quite the start to 2014. The Texan’s long-coveted swing and bat-to-ball skills appear to be in full bloom, also displaying some tantalizing pop that some felt he might not fully develop. Here’s a quick look at some of Rendon’s numbers, compared to his rookie season:

2013 394 7.90% 17.50% 0.131 0.307 0.265 0.329 0.396 0.318 100
2014 59 6.80% 15.30%* 0.273* 0.386 0.345* 0.390 0.618* 0.426* 166*

* denotes team leader

Comparing his start to 2014 to his 2013, we see Rendon is not only making lots of contact, but is making harder contact (per his isolated power), while also continuing to develop his already keen eye for the strike zone. Let’s delve a little deeper into that eye for the strike zone and its development; here, we have Rendon’s swing and contact rates for pitches in (labeled with the prefix ‘Z-‘) and out (labeled ‘O-‘) of the strike zone:

Screen shot 2014-04-16 at 9.59.42 AM

Here, we see an interesting trend—Rendon is swinging at more pitches, but making less contact compared to last season. In fact, he is swinging more at pitches outside of the zone, which is also flies in the face of his slight uptick in walk rate in 2014. Despite the slight rise in chasing pitches outside of the zone, he still shows the most restraint when comparing his O-Swing rates to his Nats cohorts; Rendon trails only Adam LaRoche and Jayson Werth with respect to Z-Contact rate (89.6% versus 90.6%), but leads the team in overall contact rate, connecting with 85.6% of pitches he has seen.

Much of this possibly points to pitchers attacking Rendon differently—is this the case? Let’s take a look at Rendon’s heatmaps for pitches seen from this and last season, courtesy of Brooks Baseball; 2013 pitches are on the left, with this year’s on the right:

Screen shot 2014-04-16 at 10.32.13 AM

By the looks of it, pitchers are taking a slightly different approach with Rendon, busting him inside with pitches more so than last year, when they went down and away with their most of their offerings. How is he faring with this tweaked approach? Let’s look at his batting average heatmaps, again with last season on the left, 2014 on the right:

Screen shot 2014-04-16 at 10.55.28 AM

The colors are a tad misleading for 2014 simply due to sample sizes—he is still making lots of contact and getting hits on pitches in the strike zone. However, we also see that Rendon is taking those inside, slightly off the plate pitches and doing more with them this year, which is not only reflected here, but in his BABIP, currently at .386.

Let’s discuss BABIP briefly. Overall, the stat doesn’t have a strong year-to-year correlation, so the chances of Rendon maintaining and continuing his current average isn’t likely. However, popup rate (PU%) is pretty correlative year to year and is also relatively predictive of BABIP. It is also a nice way to gauge how hard a hitter is hitting the ball. With this in mind, we can take a look at Rendon’s popups and not only see the potential of his BABIP to remain above average, but also how well he is hitting the ball, not only in terms of accumulating base hits, but also how hard the contact he is making really is.

Using the formula IFFB / (FB+LD+GB) * 100, we can calculate PU%. First, let’s do this for 2013:

9 / (97+73+116) * 100 = 3.16%

To put this into contrast, Joey Votto had a 0.22 PU% in 2013, having had one IFFB; teammate Bryce Harper had a 2.1% popup rate. Comparing him to a similar hitter in terms of BABIP, Manny Machado had a 5.1% popup rate.

For 2014, Rendon, like most of the league, has a 0 PU%, so we can’t really say much about popup rate improvements just yet, as we simply don’t have enough data points. However, this correlation is something to keep in the back of our minds as the season progresses. However, looking at last year’s numbers, we do see Rendon as someone who projects to hit the ball hard as he continues to develop.

Last, let’s briefly look at Rendon’s swing. Overall, it’s one that spends a long time in the strike zone, allowing for more opportunities to make contact. He does show some ‘noisy’ hands, exhibiting lots of extra movement. However, as you can see, his hands appear to be a little less noisy:

rendon3 09-09-55-127

Click to start gif

…compared to 2013:


Click to start gif. Courtesy of www.blessyouboys.com

While these gifs aren’t the best for comparison given the first is on a fastball, while the second is on a curveball, it does show the changes in how his hands and feet are set and work throughout his approach. With that caveat noted, it appears that Rendon has also removed some extra movement with his lower half, making an already compact swing quicker, allowing him to cover all corners of the plate and also turn on those high and tight fastballs he appears to be getting more of in 2014.

Despite counter intuitive statistical changes from this season to last, we see an improved approach by Rendon, possibly brought on by some slight mechanical tweaks. He is not only taking what he is given in terms of pitches in the strike zone, but is also showing pitchers that he can turn on the inside pitch, thus opening up the outside corner for Rendon in future at bats. In terms of his BABIP and the ability to consistently make hard contact, the trends bode well; however, it’s a little to early to say with much conviction whether the BABIP we have seen from Rendon in the first month of the season will remain through the year or his career, but nonetheless, we should enjoy the show one of the best pure hitters in the game is putting on.


Data courtesy of FanGraphs, unless otherwise noted


About Stuart Wallace

Stuart Wallace is a Contributor to District Sports Page. A neuroscientist by day, the Nevada native also moonlights as an Associate Managing Editor for Beyond the Box Score, stats intern at Baseball Prospectus, and a contributor at Camden Depot. A former pitcher, his brief career is sadly highlighted by giving up a lot of home runs to former National Johnny Estrada. You can follow Stu on Twitter @TClippardsSpecs.


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