If you’re thinking baseball has never seen this kind of influx of young impact players, you’re absolutely right. But if you’re thinking players are getting to the big leagues at a younger and younger age, you’re wrong.
In fact, it’s just the opposite. Of the 262 players who made their Major League debuts in 2019, the average age was 25.0 years old, according to research by MLB.com’s Jason Bernard and David Adler. That’s the 17th-oldest age for debuting players in the 144 seasons of Major League Baseball. (This data comes from the MLB debut ages that are on record, as some years of MLB history might have incomplete records.)
And that’s been the norm of late, as the average age for players coming to the big leagues over the last five seasons has ranged from 25.0 to 25.3 (in 2016).
All five of those seasons rank in the top 21 in terms of oldest average age for first-time players and a far cry from, say, 1976 when the average age was 23.3 or 1971 when the average was 23.0.
And yet…
We’re more aware of the youth because of the impact kid players are having. In the decade of the 2010s, 21 players had debut seasons that produced at least a 2.0 WAR, per Baseball-Reference. Twenty-one debut players accomplished at least a 2.0 WAR in the 2000s, as well. But in the 1980s and 1990s combined, only 12 players had a 2.0 WAR or better season in their debut.
So the data suggests that while teams are as cautious as ever about bringing young players to the Major Leagues, they’re better than ever at identifying players who can contribute immediately.
Nationals outfielder Juan Soto debuted at the age of 19 in 2018 and was scary good from the start. Likewise, Braves outfielder Ronald Acuña Jr. was 20 years old when he played his first game a few weeks before Soto.
Add to this list: Mike Trout, Cody Bellinger, Francisco Lindor, Carlos Correa and Bryce Harper. All were 21 or younger when they played their first Major League games. All five of them were almost instant stars.
Among MLB front offices there’s a consensus that explains this trend. We asked a horde of executives to explain why this has happened, and three themes emerged. They are as follows.
1. Athleticism is more valued than ever, and athleticism means younger.
Erik Neander, Rays senior vice president of baseball operations: “There’s a lot of explosive sports where that peak physical production is much earlier. Maybe it's as simple as that. Velocity tends to peak sooner. Technology and data have helped identify that. Also, players are more and more curious about some of these things, and maybe in some respects you're able to accelerate their awareness when it comes to what it takes to be a successful Major League player. You're seeing more velocity, you're seeing more power. It’s a power-speed game, and you’re trying to find ways to help players maximize themselves physically.”
James Click, Astros general manager: “It’s a gut feel, but as athleticism becomes a necessary skill to keep up with the ball moving 110 mph off the bat, it may just be that that when players peak as athletes is closer to when they peak as ballplayers as well. And it may be -- and this is just a wild guess -- that as baseball speeds up, as the reaction time shortens between when a ball is thrown and when it's hit, that places a premium on the reaction times that people have when they're in their 20s as opposed to when they're in their 30s. But it's the measure of basic skill sets that impact games and can help us win today.”
2. Technology has allowed teams to identify skills that win games.
Click: “Over the past 10 years, most of the technology that has come online has led us to find that faster is better, right? Guys who throw the ball hard, guys who hit the ball hard, guys who run faster. We can measure the impact those things have. We can quantify the difference between 88-90 mph, 90-95 mph and 95-100 mph. We’ve seen velocity trend upward steeply. And we've seen exit velocity trend upwards.”
To put a finer point on that: There once was a time when a scout’s top aid was a stop watch, and then came the portable radar gun. Now, starting as early as high school, there are tools to measure exit velocity, launch angle and bat speed for hitters.
3. Amateur players refine their skills earlier than ever.
John Mozeliak, Cardinals president of baseball operations: “I think with how amateur baseball's going, you’re certainly seeing these 18-year-olds on your radar very quickly. And then when they get on your radar, they move quickly. And I think part of that is they've been practicing certain skills that you need to get drafted. I’m not sure I’m the biggest fan of this kind of one-sport expertise, but that’s what we’re seeing. Trying to bypass the Minor Leagues or shortchange that part of the process might be dangerous, so you have to find that right balance. But clearly, you’re seeing some of the more impactful players in the game.”
Mike Elias, Orioles general manager: “I think that like any big trend, it's usually a perfect storm of purpose or multiple factors contributing. Number one, the international market is supplying more and more players, and that market has become very refined in the way those players are scouted and trained once they're brought to the United States. Likewise, I think the amateur landscape in general, there's more wood bat competition for high school kids. They’re more accustomed to travel and facing 90-mph-plus velocity.”
So when you hear someone say that we’re seeing more and more young players make debuts, feel free to gently correct them and tell them it’s actually about the quality of young players, not the quantity, that’s making a difference, and feel free to use these talking points from top MLB execs to explain why.