2020 in Review: Nathan Eovaldi

Welcome to our 2020 Red Sox in Review series. This is, as you can probably guess, where we will be reviewing all of the players who made at least a modest impact on the Red Sox in 2020. Every week day we’ll be deep diving into one player. For each edition we’ll describe the season in a sentence, look at the positives from the year as well as negatives, look back at our one big question from the season preview and look ahead to the 2021 season. We’ll be going in alphabetical order of the players on this list. You can look over that list and drop a name in the comments if you think I left anyone out who should be mentioned here. Got it? Good. Today we are exploring how 2020 was for Nathan Eovaldi.

2020 in one sentence

Nathan Eovaldi did have to spend time on the injured list again in 2020, but when he was healthy he largely looked like he did in the regular season in 2018.

The Positives

One of the bigger mischaracterizations I see regarding Red Sox players is that Nathan Eovaldi was just a playoff success story in 2018. The reality is he was very good that entire season, including before the trade when he was with the Rays. Overall, he finished that year 11 percent better than league-average by park-adjusted ERA and 13 percent better by park-adjusted FIP. And as I just said in the previous section, he was similarly good (20 percent and 12 percent, respectively) in 2020, albeit in a much smaller sample.

Photo by Billie Weiss/Boston Red Sox/Getty Images

When we were able to see him pitch, though, Eovaldi had most of us at least feeling better about his contract, if not totally satisfied. And the biggest part of his game that most resembled his impressive 2018 was his control. That season, the righty walked fewer than five percent of his opponents, but then saw that rate explode to over 11 percent last season. Where he’d land in 2020 was perhaps the biggest thing for us to look for, with the thought being he’d likely land somewhere in the middle. Instead, he was even better than 2018, finishing this past season with a walk rate of just 3.5 percent. Among the 111 pitchers with at least 40 innings, only three issued free passes at a lower rate.

There were a few keys here, but the first and most obvious was simply that he was throwing strikes more often. Eovaldi watched his zone rate fall to 48 percent (per Baseball Savant’s Statcast numbers) in 2019, the first time in the Statcast era he’s had a rate below 50 percent. In 2020, he got that up all the way to 53.6 percent, the second-highest rate of his career, only trailing 2018. On top of that, when he did miss the zone he got his chase rate back up to his 2018 levels. It’s a fairly basic formula. Throw strikes, and when you don’t then get chases.

Along with the lack of walks, Eovaldi also racked up strikeouts at a rate we’ve never seen from him before. Part of that is certainly just being risen by the tide that is the league-wide strikeout rate. Batters are changing their swings, and it’s simply easier to get strikeouts than ever. But it should also be mentioned that Eovaldi improved his swinging strike rate both in and out of the zone.

From an arsenal perspective, the biggest key to the swinging strike rate, and his overall success, was the secondaries. Eovaldi is mostly known for his big velocity, and that is certainly not a bad thing. His average fastball came in at 97 mph this past summer, right in line with where he’s been throughout his career. It’s what he does when he doesn’t show off the velocity, though. And more specifically, in 2020 that meant his curveball and his splitter. Of his four offerings, those were the two he threw the least, but they also saw the biggest jump both in terms of overall performance against them as measured by wOBA in the case of the curveball as well as in terms of swinging strike rate in the case of the splitter. Eovaldi’s fastball has always been fast, but relatively flat, so being able to have hitters thinking about these slower offerings with more movement makes him a more complete pitcher with a much greater chance of success.

The Negatives

It wasn’t a totally flawless season for Eovaldi, and the biggest issue has to be his health, which has been a theme throughout his career. It always makes me a bit uneasy to talk about injuries in terms of negatives as it can imply that it’s the player’s fault, which simply isn’t the case. Eovaldi isn’t trying to get hurt, nor is he refusing to pitch when he’s able to or anything like that. Injuries happen, and sometimes certain bodies are more prone to being hurt. All that said, Eovaldi is an important player on this roster and the Red Sox need him on the field as much as possible. To be fair it wasn’t a major injury as he only missed a few turns with his calf injury, but three starts in a 60-game season is a significant chunk. Over a full season, at this point the hope has to be for something like 25 starts a year for Eovaldi.

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Beyond the health, though, there really wasn’t too much to complain about. He was able to control the strike zone extremely well with his strikeouts and walks, but he did have a bit of trouble with balls in play. To be fair, that is more likely to have noise in small samples like Eovaldi’s 48-inning sample, but he was hit hard. The righty allowed a batting average on balls in play of .336, his highest since 2015, as well as allowing eight homers in nine starts. According to Statcast numbers, he was in the bottom third of the league in average exit velocity, barrel rate and hard-hit rate, all of which were in line with his 2019 numbers.

The Big Question

Can Nathan Eovaldi’s cutter be a weapon again?

When Eovaldi was able to break out in 2018, the biggest reason was that he brought the cutter back into his arsenal after ditching it early in his career. It was a total gamechanger for his approach and directly led to the major improvements he saw that year. In 2019, though, the book was out and that combined with a lack of command on the pitch saw a major regression. He needed to find a way to make this an effective offering again.

As it turned out, it wasn’t quite as important as I had anticipated, but it still did improve. In terms of performance against the pitch measured by wOBA, Eovaldi landed somewhere in the middle of 2018 and 2019. That was important for him to claw his numbers back to respectability, but really it was what we discussed above with the splitter and curveball that made him so effective. The takeaway is that he needs secondaries to perform near his ceiling. The cutter was important, but as long as he has something to turn to beyond the fastball, he can put up impressive numbers.

Looking ahead to 2021

Eovaldi should be part of the rotation again in 2021. With his contract there may be some trade speculation, but after what he did this past summer his contract is closer to even value than it had seemed at this point last year. For a team that desperately needs pitching, trading him just to shed salary wouldn’t make sense. It will be another long year if he’s miscast as a top-of-the-rotation arm again next year, but that will be a problem with roster construction, not him. The reality is he’s a perfectly cromulent mid-rotation arm, injury woes and all.