Coming into the season, Nathan Eovaldi was entering an impossible situation with too much on his plate. It certainly wasn’t his fault, but with Chris Sale’s injury, Eduardo Rodriguez’s health issues, and David Price being traded to Los Angeles, Eovaldi was thrust into an “ace” role. Whether or not you define ace as anyone at the top of a rotation is picking nits, but the important part was that he Eovaldi came in as the number one for Boston, a role for which he frankly is not suited. As it turned out, our fears about this rotation were somehow not strong enough, and Eovaldi ended up being at the head of a historically bad group. This fact ended up masking that the righty actually turned things around in a big way and had himself a very successful 2020 season.
Now, it certainly was not a perfect season for Eovaldi even if you remove the disaster that was the rest of the roster. The biggest concern for him throughout his career has been injury, and he missed some time this year as well. On the other hand, it wasn’t an arm injury this time around but rather what was originally called a calf cramp that caused him to miss just a couple weeks. In a regular-sized season, that amount of time wouldn’t really be noticed. In 60 games, it certainly was. When he was able to pitch, though, Eovaldi ended up being as good, or maybe better depending on your metric of choice, than he was in 2018.
Wednesday night was the final look we’ll get at the righty this summer, and he finished things off with a bang. Going up against an Orioles team he had dominated a couple times already this season, Eovaldi tossed six scoreless innings with eight strikeouts and just one walk. That was an extension of his season as a whole, which finished with 48 1⁄3 innings to go with a 3.72 ERA (81 ERA-) and a 3.86 FIP (88 FIP-). By those park-adjusted numbers in which anything under 100 is better than league-average, he was eight points better compared to 2018 by ERA and one point worse by FIP. Prior to this season, 2018 was clearly the best season of his career, even if we ignore his heroic playoff run.
There’s a lot to cover about what Eovaldi did this season and we’ll surely examine it in detail as the offseason goes on, but the one part I want to focus on right now is his control. Looking at how last season’s disappointing campaign compared to that 2018 season, there were a lot of issues, including health perhaps at the top of the list. On the statsheet, though, the one number that stood out like a sore thumb was his walk rate. After riding a 4.4 percent walk rate to success a couple of years ago, he almost tripled it with an 11.6 percent rate in 2019. After two starkly different years, I was curious which end of the spectrum he’d be closer to in 2020. As it turns out, he went off the spectrum, walking 3.5 percent of his opponents this season.
That is clearly an elite rate, and among the 104 pitchers with at least 40 innings this season, only four (Zac Plesac, Marco Gonzales, Kyle Hendricks and Zack Greinke) walked batters at a lower rate. Speaking only of Eovaldi, expecting that kind of number specifically moving forward is probably silly given the small sample size and the fluctuation he’s experienced in his career.
This is not to say there are not actual encouraging signs, however. The veteran righty has shown some signs of real changes that have led to this improved rate. For one, he is simply hitting the zone more. Per Baseball Savant, he fell down below 50 percent with his zone rate for the first time in 2019, but in 2020 he’s jumped back up above that threshold by a safe margin. Furthermore, when he does hit the zone he’s getting chases at the same rate he did in 2016 and 2018 (he missed all of 2017). In 2019, that rate fell significantly. If you are hitting the zone and getting swings when you don’t, clearly you’re not going to walk a lot of batters.
The key to all of this has been his secondaries. Eovaldi is mostly known for his fastball, which makes sense because he touches triple digits with some consistency. The fastball jumps off the page. It’s actually a little on the straighter side, though, and on its own isn’t all that impressive beyond the velocity. For his arsenal to work, he needs the secondaries. A lot of that has to do with his cutter. This was the pitch he brought back into his arsenal in 2018 with the Rays and it was the main reason for his breakout that season. Last season, however, batters appeared to have adjusted. According to Brooks Baseball, opponents swung at the pitch just 40 percent of the time compared to 57 percent of the time in 2018. This is important, since ideally a cutter starts on the plate but ends up breaking off of it. If batters are laying off, it’s an easy way to fall behind in counts. This season, though, that swing rate is back up to 58 percent.
No pitch exists in a vacuum, of course, and while the cutter has looked sharper this year — Baseball Savant indicates the horizontal movement on the pitch has increased significantly — he also continued to emphasize another secondary. Eovaldi started throwing his curveball a lot in 2019, and this year he’s continued to do so. That pitch being a threat along with the sharper cutter has achieved the goal of hitters staying off balance and getting them to swing at those pitches off the plate.
Eovaldi is never going to be a pitcher for whom you feel 100 percent confidence, partly due to health reasons and partly due to inconsistency in numbers year to year. That said, he’s shown in two of the last three years that he can be very good. It was never fair to cast him at the top of the rotation and they’ll be similarly in trouble if they enter 2021 with him in the same role. That said, he’s continuing to evolve as a pitcher and reminded us this summer that we can feel comfortable with him in a supporting role, at the very least.