Julio Urias, the Dodgers, and the History of Teenage Pitchers

For all her conspicuous virtues and manifest talents, late singer Aaliyah was almost certainly mistaken in her assertion that age “ain’t nothing but a number.” It is a number, that’s true, but it’s a number that represents the number of years a thing or person or some other manner of noun has existed. Which, that’s more than nothing.

In the context of baseball prospect analysis, age is decidedly not nothing. As both anecdotal evidence and also more rigorous statistical evidence* suggest, age relative to level is predictive of future major-league performance, where younger relative to level is better. One finds, for example, that players who debut at a younger age produce higher prorated WAR figures than players who debut at an older one. It’s not because they’re younger that they’re better, of course. Rather, their respective teams have generally recognized that they’re capable of handling the highest level of competition. And it follows that, if they’re able to handle that level of competition en route to their respective peaks, then they’re also generally able to handle it in the decline phase of their careers, too.

*Such as the sort produced by Chris Mitchell.

The relationship between age and performance and level is the foundation for the considerable and deserved excitement regarding Mike Trout’s career — not only for his career up the to present day, but also the prospect of what his career will have been once it’s finished. Trout has recorded the highest WAR among all hitters ever through his age-22 season, for example. That’s not only impressive, but probably also predictive. Because consider: basically all of the next 20 guys on that particular leaderboard are now in the Hall of Fame.

Players who, like Trout, combine youth and talent are notable. And, all other things being equal, it’s reasonable to expect that the prospects who are producing the top performances at the youngest ages will develop into the best players.

This question of talented youth is relevant today largely because of the Dodgers, their rotation, and their top pitching prospect left-hander Julio Urias. The Dodgers possess the largest major-league payroll by roughly $50 million. They also possess the sort of expectations associated with that kind of payroll — and, over the first month of the season, the club has more or less met those expectations. As of today, for example, they lead the NL West by two games and feature nearly a 90% chance of winning that division according to the numbers and methodology used at this site.

But the club’s roster isn’t constructed flawlessly. Rather, it’s imbalanced perceptibly in favor of hitters. Indeed, the Dodgers feature such a glut of position players that finding at-bats for Alex Guerrero — a batter who’s recorded more than two extra-base hits for every strikeout — has been difficult. Because of injuries to Brandon McCarthy and Hyun-Jin Ryu, meanwhile, the club has been compelled to give starts to Scott Baker, Mike Bolsinger, and David Huff. This isn’t to cast aspersions against any of that triumvirate. It is to observe, however, that a club which possesses both the Dodgers’ means and expectations would ideally like to enter May before turning to a cast of minor-league free agents.

The Dodgers do, however, have another option, and it’s Urias. It’s only a theoretical option at the moment because Andrew Friedman announced earlier this week that Urias isn’t being considered as a replacement for McCarthy. But Urias’s credentials are impressive. He features a fastball, curve, and changeup that all profile as above-average or better already. He’s finished among the leaders at Class-A and High-A over the last two years, respectively, by strikeout- and walk-rate differential (i.e. the best small-sample proxy for performance). So far this year, he’s produced the second-best strikeout- and walk-rate differential among all qualified pitchers in Double-A — behind only a 26-year-old Rangers prospect named Chadwick Bell. And at 18, he’s not only the youngest player in all of Double-A, but would also be the youngest at High-A had he not already acquitted himself excellently against the opposition at that level.

It would seem that there’s very little keeping Urias from a spot in the Dodgers rotation at this point. Little except that it basically doesn’t ever happen in modern baseball.

Curious, I endeavored to find some situations comparable to the one Urias could theoretically find himself. Were the Dodgers to move him directly into the rotation but also protect him a little bit, I reasoned — with the knowledge, as well, that he recorded only 87 innings last year — it’d be possible maybe for him to make about 20 starts of approximately 5.0 innings each, or 100 innings total.

Turning to the leaderboards here, I set the relevant criteria. And here are the results of that search — a complete list of teenage pitchers who’ve recorded at least 100 major-league innings in one season since 2000:

Zero, in other words, is how many teenage pitchers have recorded 100 innings in a season since the start of the millennium. Nor did any of them do it in the 1990s, either. Indeed, one must go back to 1984 to find an instance of a teenager throwing more than 100 innings. It was a 19-year-old Dwight Gooden, and he actually threw 218 innings, producing a 48 FIP- and 8.3 WAR. That’s an impressive return, of course, but also (a) it amounts to an n of just 1 and also (b) it’s difficult to ignore the fact that, apart from some obvious professional success, that Gooden also faced conspicuous troubles. Whether those troubles were a direct result of the age at which he debuted — that’s outside of the scope of this post. But it’s not a great indicator, is the point.

Before Gooden was David Clyde in 1974 — which (in addition to Gooden’s own difficulties) probably helps to explain why teams have been reluctant over the past 40 years about giving significant major-league time to teenage pitchers. The left-handed Clyde, notably, was drafted as an 18-year-old by the Rangers out of Texas A&M in 1973 and inserted directly into the major-league rotation. He recorded about a win in 93.1 innings that season, produced negative value over 117.0 innings in ’74, and then proceeded to appear in only three different seasons after that. So, not a success, either.

This isn’t to say that zero teenage pitchers have made any sort of appearance in the contemporary game. It is to say, however, that only four of them have. Here are the results, in order by innings pitched:

So, four guys. Two are really good, one’s had his moments, and one (hopefully) has some moments ahead of him. As a group, however, they’ve pitched only slightly more than 100 innings total — and, one notes, they’ve all done it as 19-year-olds. Urias remains still in the midst of his age-18 season. So, while he might possess a lot of the physical tools one finds among major-league pitchers, he doesn’t possess an age that has been seen in the majors for a long time. And that’s very likely not lost on Andrew Friedman and the his colleagues in the Dodgers front office.