It’s safe to say that Eduardo Rodriguez has not had a stellar May. In 25 innings pitched, the lefty has allowed 38 hits and an OPS of .952 to opposing batters, contributing to a poor 6.48 ERA for the month. Some have wondered whether he’s still being affected by his scary bout with COVID-19 last year, or if he’s just rusty after missing all of the 2020 season. I can’t speak specifically to what he’s feeling, but I feel confident saying that there isn’t anything big to worry about.
Simply put, there just aren’t many red flags in E-Rod’s underlying metrics so far. His fastball and cutter velocity are right in line with where they were in 2019. He’s not giving up harder contact this year –- his exit velocity and hard-hit rate allowed are similar to his career averages. Additionally, Rodriguez’s strikeout and walk rates are among the best they’ve ever been. Why haven’t the results come yet?
As is the case for Nathan Eovaldi, Rodriguez has been a victim of poor luck. He has a lower-than-league-average LOB% (left-on-base rate) of 70.4 percent, and his batting average on balls in play is way up at .363 – much more inflated than his career BABIP of .304. While Rodriguez’s ERA looks ugly at 5.06, his FIP and xERA (which factor in the above numbers) are at a solid 3.55 and 3.45, respectively. Simply put, more balls are falling in than normally should, and more runners are coming in to score than normally should. Once these numbers settle back in at the league average, I’d expect his ERA to shrink accordingly.
However, this isn’t to say that Rodriguez has been perfect. In particular, his slider has been quite ineffective this year, and it’s really been ineffective for the past few years. He’s throwing the pitch 8.7 percent of the time, which isn’t all that much, but it’s still been crushed to the tune of a .439 expected wOBA. In fact, E-Rod’s slider hasn’t allowed an xwOBA below .400 since 2016! His slider (typically a put-away pitch) isn’t generating swings-and-misses either, with a whiff rate below 17 percent. For reference, Eovaldi’s slider is getting swings-and-misses 38 percent of the time.
The main reason for Rodriguez’s struggles with his slider has been his inability to consistently locate it. As you can see in the chart below, the pitch has been all over the place, and frequently thrown middle-middle.
Now, compare that to Eovaldi’s slider location below. Everyone is susceptible to hangers, but Eovaldi has really kept the ball low in the zone and on the corners. His precision with the pitch is clearly paying off in ways it isn’t for Rodriguez, as his slider has generated the most whiffs out of any pitch in his repertoire.
I’m not exactly sure what the remedy is for this, but there are a number of adjustments Rodriguez can make. He can throw the pitch less, drop the pitch, or try and implement a new breaking ball. He experimented with a curveball a bit in 2019, throwing it about 3% of the time, and it produced solid results (.225 xwOBA). He obviously didn’t pitch at all in 2020 and has yet to bring the curveball back in 2021. When Nathan Eovaldi was struggling with his slider, he simply dropped it for all of 2020, worked on it in the offseason, and brought it back better than ever this year. Perhaps like Eovaldi, Rodriguez just needs to work on the pitch.
To conclude, even with his struggles with his slider, Rodriguez has been solid and I expect him to turn it around as his sample size increases. He’s definitely been a victim of poor luck and his metrics show that he deserves better than his ERA portrays. Four of his five pitches (fastball, changeup, cutter, sinker) have been great, and I think he’ll lean even more heavily on them if his slider continues to be hit like it has. However, in the long run I’d love to see him work on or make an adjustment with his breaking ball, and potentially take his game to another level.