Somebody Save Julio Rodríguez

When the 2022 season opened to fanfare and excitement, one of the main talking points was the record-setting arrival of top prospects. After countless rebuilds, a global pandemic, and a prolonged lockout, fans deserved to watch budding superstars duke it out in games that matter. Some of them, like Seiya Suzuki and Jeremy Peña, have been thriving right out of the gate; both rank among the top ten in batter WAR as of Thursday’s games. Others like Spencer Torkelson might have fallen a bit off the radar but have still been successful per wRC+ or batted ball metrics.

Much to our annoyance, though, there’s always a flip side we’d like to ignore. Enter Julio Rodríguez, whose triple slash of .136/.208/.159 is terrible not just amongst fellow rookies, but also all of major league baseball. This isn’t to say we should be concerned; Rodríguez remains one of the most talented rookies around, and in the grand scheme of things, 12 games and counting mean next to nothing. Don’t smash that emergency glass just yet!

But in his opportunities to prove himself, Rodríguez hasn’t been offered fair terms. One of the most fundamental and effective traits a hitter can possess is plate discipline, which is partly the ability to ignore unfavorable pitches. It’s something Rodríguez has demonstrated several times in a limited number of plate appearances, with confidence to boot, but that bravado hasn’t quite translated into results:

This is a chart showing all eight (!) called third strikes outside the zone against Rodríguez, a league-leading total. The plotted strike zone is adjusted for his height, by the way, so there’s no ambiguity here. It gets even worse when you actually look at some of these pitches, which the umpires gift-wrapped for pitchers who made objective mistakes. For example, here’s a Sonny Gray sinker that is rarely, if ever, called a strike, especially in a two-strike situation:

Uh-huh. Sure, that’s totally a decision befitting a stadium named Target Field.

You could maybe argue that Rodríguez, whose two-strike swing rate of 40.3% is the third-lowest among all hitters, needs to up his aggression. The cost of taking a third strike is high, so the math tells us that a batter ought to hack away instead. But Suzuki has a similar two-strike swing rate (42.7%), and he’s yet to be punished for his passivity. Whatever flaws Rodríguez might have right now as a hitter don’t excuse the fact that very few calls have went his way. This is a clear problem, one that has Mariners fans understandably angsty.

Naturally, Rodríguez’s string of misfortunes piqued my curiosity. What I first looked at is the track records of home plate umpires who have officiated Mariners games so far. If they’re known for mishaps, that would make me feel a teeny bit better about Rodríguez moving forward; umpire quality tends to come and go, so it’s good that he’s gotten the bad ones out of the way. In the table below, you’ll find the dates on which those inexcusable called strikes occurred, the umpires responsible for them, and their career accuracy rates, all courtesy of the Umpire Scorecards website:

Well, this is far from satisfying. Here is a mixed bag of umpires: some not very accurate, about average, or excellent across a sample of multiple seasons. There’s no motley crew of incompetent umps conspiring against our young protagonist; what’s shown above seems like the result of picking five of them at random. Any individual, regardless of their aptitude, is capable of committing an error. Perhaps it just so happens that Rodríguez was caught in the middle of eight such instances.

Not willing to let go just yet, though, I next considered the fact that Rodríguez is young, even for a hitter in his first year. If there’s anyone who might abide by the archaic notion that rookie players must earn their place in the bigs, it’s a curmudgeonly umpire. Are all those called strike threes outside the zone a sign of disrespect? Is Rodríguez being penalized for his relative lack of experience? And if so, are older veteran players more likely to have close calls go their way?

To investigate, I sorted every player season from 2015 to ’21 with minimum 100 plate appearances into five different groups by age, then worked out what percent of taken pitches in the “Shadow” zone were called strikes. That’s the region Baseball Savant defines as the borderline between a strike and a ball. For context, 47.2% of all “Shadow” pitches in the Statcast era have been deemed strikes, which makes sense; when the placement of a pitch is vague, you would expect it to go either way at equal probability. After giving more or less weight to certain players based on how many pitches they took, here are the numbers I ended up with:

There’s some disparity between different age groups, but not to an extent that would actually matter. The biggest drop-off in called strike rate occurs between ages 24–27 and ages 28–31, but it equates to a loss of four called strikes per 1,000 takes, which (a) is not recognizable whatsoever and (b) has a microscopic impact on offensive performance. Interestingly, it’s the oldest players who see the highest rate of called strikes on borderline pitches. I’m not sure what that indicates or what’s responsible for it, but I appreciate a subversion of expectations.

We’re not here to focus on what a 37-year-old Rodríguez might go through, though; we’re here to focus on the Rodríguez of now. And so far, we’ve yet to unearth an explanation for his current woes. But there is one more angle worth approaching. Maybe what matters more so than a player’s age is his service time. Maybe, rather than how old a player is, umpires are aware of whether he’s new or not. And the more familiar a player becomes to an umpire over the years, maybe the more likely he is to be remembered and receive the benefit of the doubt on close pitches. Sounds plausible enough to me.

It’s time for more methodology talk! This one’s a little tougher to lay out, but here goes: Among the player seasons in my previous sample, I identified which were from rookies. Doing so allowed me work out, for example, that if Miguel Sanó’s 2015 represents his first season, then 2016 must be his second, 2017 his third, and so on. Afterward, I looked at the change in called strike rate between a player’s rookie season and subsequent ones. In theory, the negative difference between year one and year six should be greater than that between year one and year two: more exposure (to umpires), fewer strikes. That was the idea, at least. But hypotheses are all too often proven wrong, as is the case here:

Based on this, it seems as if the longer someone has been a major leaguer, the greater the difference is between his most recent called strike rate and his rookie season rate. But it’s not necessarily because hitters with more experience are subject to more strike calls. Rather, it’s because hitters who eventually made it to years four, five, or even six started off with a lower baseline called strike rate. Consider that among the players I analyzed, those with just two years averaged a rookie season rate of 47.3%, whereas the select few with six years averaged a rate of 46.4%. That isn’t a huge deviation, mind you, but it’s significant compared to the age-based numbers from earlier. Maybe it’s good hitters who are favored by umpires!

Circling back to Rodríguez, if you’re willing to put any stock into my findings — which, admittedly, amounts to junk math — then there’s reason for optimism. Barring a developmental catastrophe, Rodríguez seems like a hitter with a long, prosperous career ahead of him, meaning his high rate of called strikes is more likely to be corrected. But really, the heart of the matter here is sample size. Looking through my data, the outliers are players who saw the fewest number of pitches, and even they saw far more of them than Rodríguez has so far this season. Other than wait, there’s nothing much we can do. Again, 12 games aren’t enough to account for anything, let alone something as fickle as all this. Only time itself can save Julio, as exasperating as that sounds.