And 25-and-unders represent 26.3 percent of the full rosters of All-Stars. Of the 76 players in Cincinnati tonight, 32 will suit up as All-Stars for the first time.
Call it what you will -- an influx, a revolution, a perfect storm -- but the presence of youth in today's game cannot be denied or underestimated.
"I played against a lot of these guys in the Minors," said Rockies third baseman Nolan Arenado, who at just 24 is often overlooked among the young stars. "To be here at the same time, it's definitely a lot of fun, and it shows a lot of hard work. I work hard because I know those guys are working hard. That's something I take to my game: I don't want anyone to ever have an upper edge on me. That's something I take personal.
"I played against Harper, I played against Trout. I played with them in the Fall League All-Star Game. There's a couple guys; I can't even name them all. A.J. Pollock is one of them. Now to be here together is a lot of fun. It's a lot of fun. "
Perhaps Bryce Harper summed it up best: "I guess it's a young game now."
Harper, at 22 (22 years, 8 months, and 28 days, to be precise), is the youngest All-Star of them all. Harper also holds the record for youngest position player in All-Star history, at 19 years and 268 days in 2012. Overall, he's second only to Doc Gooden, who in 1986 made his All-Star debut as a pitcher at 21 years, 7 months and 30 days.
"It's good to have some young talent here," Mike Trout offered. "Guys that come here, make an impact for their team, it's pretty special. I'm happy for them."
Given the sport's rich history, some may grumble about the fact that the kids are running The Show.
They shouldn't, according to elder statesman Albert Pujols, who has 14 years of big league service time. Harper was 8 when Pujols made his Major League debut in April 2001.
"I'm pretty sure I can say the same thing [about youth in the game] back in the start of my career in 2001," he said. "We had the guys -- Roy Oswalt, Ben Sheets, Albert Pujols, Prince Fielder. I mean, you're always going to have a [young] generation like that. That's why this game is so good.
"Five years from now, we're going to be talking about a [Carlos] Correa kid. [There are] players coming up through every system through the Minor Leagues, and that's why baseball has gotten so much better."
"The game's evolving into a younger sport," said Harper, who garnered the most votes in the NL this year. "I think everybody can see that. I think everybody knows that. It's a lot different than it used to be. You've got guys coming out of the 'pen and throwing 100 [mph] every single time. You've got starters going out there doing what they do, then a relief pitcher coming out to face a lefty for one at-bat, going into the dugout and sitting down.
"It's a lot of different things going on. I definitely respect the way people played back in the day. Always have. But the game's definitely changing. It's a younger and more international sport, and that's very exciting for the game of baseball."
The general consensus around the game -- and in Cincinnati for the Midsummer Classic -- is that all is as it should be.
"If you're young, but you can play, you're going to stay here. You belong here," said Jose Altuve, who at 25 is already in his third All-Star Game. "A lot of guys are showing it. A lot of them are 25 and younger that are playing the best. They deserve to be here."
There has been a paradigm shift in Major League Baseball, to be sure, and a good one at that.
"It's special to see so many great players at such a young age," said Pederson. "The Trouts, Harpers, they're dominating the game. [And] just look at [Madison] Bumgarner and [Anthony] Rizzo ... guys who have been in the league a few years, yet they are still pretty young players. Those guys are unbelievable."
The man who goes by "Young Joc" on Twitter (@yungjoc650) and his compatriots are doing their best to soak in their veteran teammates' presence tonight.
"It's a great experience," said 25-year-old Tigers shortstop Jose Iglesias. "I get a chance to talk to all of them, learn something from all of them. I think that's what it's all about, get to know all the guys in the league, learn something from them. I had a 20-minute conversation with Pujols talking about everything on and off the field. I think those are little things that make you -- as a player and a human being and as a person -- better. I think that's why you came here, to talk to those type of guys who have been around for a long time.
"I'm glad to have that in Detroit, as well. We have Victor [Martinez], Miggy [Miguel Cabrera and Ian] Kinsler, but I think it's special to listen from other organizations, from other perspectives. I'm really happy about that, to share the experience."
Not only share the experience, but carry the mantle of Major League Baseball, too.
In the words of Harper: "We're just trying to build it and keep doing what we need to do to try to enjoy it, and just take it all in."
Megan Zahneis is a reporter for MLB.com. Alden Gonzalez, Anthony DiComo, Mark Sheldon, Corey Brock, Alyson Footer, Mark Newman and Jason Beck contributed reporting. This story was not subject to the approval of Major League Baseball or its clubs.