If we had to pinpoint the one theme of this 2015 season that stands out above all others, it's unquestionably the dominating impact and the infusion of youth on the Major League scene. Never was this more evident than on Monday night when 23-year-old Cubs rookie Kris Bryant cracked his first career walk-off homer into the Wrigley Field bleachers to give the Cubs a dramatic 9-8 win against the Rockies.
And just an hour or so before Bryant's blast landed, the mere suggestion that the Dodgers might consider trading 24-year-old Yasiel Puig turned social media upside down.
Be it the promotions of prominent prospects -- such as Bryant and Carlos Correa -- who were household names before they even reached the bigs or the stunningly swift maturation of guys barely old enough to rent a car -- think Bryce Harper and Carlos Martinez -- it's become abundantly clear that the game's present and future are in great hands.
"The group of young players that we have today is just absolutely outstanding," Commissioner Rob Manfred said. "They're great on the field. They're really great human beings off the field. And I think they provide a real opportunity for the game to move forward."
To wit, this year's All-Star Game rosters featured 20 players age 25 or younger -- the most in history -- and 11 of MLB's 30 teams reached the midway mark with a player 25 or under leading them in Wins Above Replacement. If that holds true at season's end, it would mark the first time since 1980 that so many teams were led in WAR by players that young.
And as we showed yesterday, additional data further backs this up. We are in the midst of a golden generation of young talent in the game.
With that in mind, here are our Top 25-and-Unders, our ranking of the top 25 players age 25 and younger. All players who were 25 and under as of July 1, 2015 -- their age-25 season or younger -- were eligible for votes, and the list was selected by a panel of MLB.com and MLB Network analysts, including two former Major League general managers, Dan O'Dowd and Jim Duquette.
"There are so many talented 25-and-under players in the game right now that it easily could have been a top 50 list," said O'Dowd.
Here is how the vote turned out, with a look at how each player rose to prominence.
1. Mike Trout, Angels, CF (age 23)
Born: Vineland, N.J.
HS: Millville (N.J.) HS
Twenty-four players were taken before Trout in the 2009 Draft. He is from Millville, N.J., so his high school career wasn't heavily scouted, and there was some hesitation in the industry about his level of competition and his rawness. So he sat there alone, hanging on every pick, at the MLB Network studios on Draft day until the Angels, who could afford to take some risk with five of the top 48 selections in that Draft, made his wait worth it. Trout has been making history ever since, winning one American League Most Valuable Player Award, the AL Rookie of the Year Award and two consecutive All-Star Game MVP Awards, all before his 24th birthday.
Video: 25 and Under: Outfielders dazzle around MLB
2. Bryce Harper, Nationals, OF (age 22)
Born: Las Vegas
HS: Las Vegas HS
College: College of Southern Nevada
At 12 years old in 2005, Harper became the youngest player ever to attend a Perfect Game showcase, and even then his powerful swing and his athleticism were raising eyebrows. At 16, he was on the cover of Sports Illustrated. At 17, having earned his GED to jump-start his Draft eligibility, Harper was the No. 1 overall pick by the Nationals. At 19, he won the National League Rookie of the Year Award. And at 22, Harper is in the midst of a major bid for the NL MVP Award.
3. Manny Machado, Orioles, 3B (age 23)
Born: Hialeah, Fla.
HS: Brito Miami Private School (Miami)
As a Miami native of Dominican Republic descent, Machado heard the Alex Rodriguez comparisons long before he went pro. But he also made a name for himself by leading USA Baseball's 18 & Under team to a gold medal in the Pan American Junior Championship, and the Orioles took the athletic shortstop with burgeoning power and defensive prowess at No. 3 overall in 2010. Though knee woes hindered Machado in '13 and '14, he's been a legit superstar this season.
Video: 25 and Under: Correa, Machado highlight infielders
4. Giancarlo Stanton, Marlins, OF (age 25)
Born: Panorama City, Calif.
HS: Notre Dame HS (Sherman Oaks, Calif.)
Stanton was a three-sport star in high school, and he might have been an even better receiver and rebounder than he was a baseball player, which helps to explain why he went to the Marlins in the second round of the 2007 Draft, not the first. But once his attention was no longer divided, he began to take off. According to Statcast™, Stanton has hit five of the 13 longest homers this season, despite missing the past month with a broken hand.
5. Sonny Gray, A's, RHP (age 25)
Born: Nashville, Tenn.
HS: Smyrna (Tenn.) HS
College: Vanderbilt University
The youthful-looking Gray could be mistaken for a high school kid -- until he takes the mound. He had his coming-out party in the 2013 AL Division Series, when he was a little-known rookie who had two fantastic duels with Justin Verlander. Since then, Gray has established himself as the A's ace, with crazy movement on pitches that seem to have a mind of their own. He is used to being on center stage, having not only led his football to two state championships as the starting quarterback, but also starring in a school production of "High School Musical."
Video: 25 and Under: Young arms dominate around MLB
6. Jose Fernandez, Marlins, RHP (age 22)
Born: Santa Clara, Villa Clara, Cuba
HS: Braulio Alonso HS (Tampa, Fla.)
The lightning-armed Fernandez has said he takes a look at himself in the mirror every morning and reminds himself where he came from. He unsuccessfully tried to flee his native Cuba and was imprisoned three times. On the fourth attempt, the boat Fernandez was on was peppered with bullets by Cuban soldiers, and his mother fell off the boat and nearly drowned. Somehow, he made it to Miami, settled in Tampa and developed into an elite arm, getting drafted at 18 and finishing third in the NL Cy Young Award voting in his 20-year-old rookie season for the Marlins. Now Fernandez is back from Tommy John surgery to continue his journey.
7. Madison Bumgarner, Giants, LHP (age 25)
Born: Hickory, N.C.
HS: South Caldwell HS (Hudson, N.C.)
A three-time World Series champion with one of the best all-time October résumés, all before the age of 26. Not bad for a kid from small-town North Carolina, one who was so homesick after he first signed with the Giants and went to instructional league that he considered quitting the game.
8. Carlos Correa, Astros, SS (age 20)
Born: Ponce, Puerto Rico
HS: Puerto Rico Baseball Academy (Gurabo, PR)
As a kid in Puerto Rico, Correa began helping his father, a construction worker, on job sites when he was just 8. Working in the heat convinced him that he'd better get really good at baseball, so that hard labor would not be the focal point of his future. With stunning athleticism and growing power, Correa is a remarkably mature person and player at 20, already impacting the Astros in a major way and rewarding their decision to make a 17-year-old slugging shortstop the No. 1 overall pick in the 2012 Draft.
9. Anthony Rizzo, Cubs, 1B (age 25)
Born: Fort Lauderdale, Fla.
HS: Stoneman-Douglas HS (Parkland, Fla.)
Rizzo has leaped over every hurdle he's encountered on his ascent to star status. He was diagnosed with limited stage classical Hodgkin's lymphoma. Rizzo was traded twice before the age of 23. He heard the scouts and the skeptics who first said he couldn't catch up with high-velocity fastballs and then questioned his ability to hit lefties. Rizzo has overcome all of that to become a two-time All-Star and a cornerstone for the improving Cubs.
10. Gerrit Cole, Pirates, RHP (age 24)
Born: Newport Beach, Calif.
HS: Orange Lutheran HS (Orange, Calif.)
We got our first glimpse of Cole during the 2001 World Series, when the 11-year-old was shown on TV with a sign that said "Yankee Fan Today Tomorrow Forever." Seven years later, the Yankees drafted him 28th in the first round … and Cole turned them down, opting instead to continue his education at UCLA. Three years after that, the Pirates got him at No. 1 overall, and he's since ascended to the forefront of their rotation with nasty stuff and leadership qualities.
11. Kris Bryant, Cubs, 3B (age 23)
Born: Las Vegas
HS: Bonanza HS (Las Vegas)
College: San Diego
If you think those Cubs-Nationals games featuring Bryant and Harper are fun, you should have seen them when they were a couple of 9-year-olds playing against each other in the Las Vegas area. Bryant took a different, more traditional path to the big leagues, opting to attend the University of San Diego after the Blue Jays drafted him in the 18th round in 2010. Three years later, the Cubs got him with the second overall pick, and two years after that, Bryant earned All-Star honors a little more than two months into his MLB career.
Video: COL@CHC: Bryant walks Cubs off with two-run homer
12. Nolan Arenado, Rockies, 3B (age 24)
Born: Newport Beach, Calif.
HS: El Toro HS (Lake Forest, Calif.)
Arguably the best defensive third baseman in baseball, Arenado was actually thought to perhaps be in line for a position change when he was drafted 59th overall out of high school in 2009. Some questioned his footwork and wondered if his future might be in the outfield or at first base. But the emerging star for the Rockies erased all doubts with his range and arm strength, and Arenado's bat was always an asset.
13. Jose Altuve, Astros, 2B (age 25)
Born: Maracay, Venezuela
The littlest guy on this list is also one of the most productive. Listed at 5-foot-6, Altuve has a presence bigger than his body. At 16, he was cut from his first tryout camp with the Astros in his native Venezuela, but he showed up the next day and told the evaluators, "Don't judge me by size, but how I play." Altuve earned a $15,000 signing bonus, and his steady bat and fleet feet allowed for an ascension to the big leagues, where in 2014, he became Houston's first batting champion.
14. George Springer, Astros, OF (age 25)
Born: New Britain, Conn.
HS: Avon Old Farms School (Avon, Conn.)
Only a broken wrist could stall what has been a steady rise to star status for Springer at the big league level. The Astros grabbed the UConn product with the 11th overall pick in the 2011 Draft, and they liked him so much that they tried -- unsuccessfully -- to sign him to a long-term extension before he even set foot in the big leagues. Springer arrived in 2014, and his combination of power and speed make him a threat to join the 40/40 Club.
15. Freddie Freeman, Braves, 1B (age 25)
Born: Fountain Valley, Calif.
HS: El Modena HS (Orange, Calif.)
The Braves drastically overhauled their roster over the winter, but Freeman's productive bat remains the organizational cornerstone thanks to the now rare ability to hit to all fields with power. A dual citizen of the U.S. and Canada (where his parents were born), Freeman was the 2011 NL Rookie of the Year Award runner-up to teammate Craig Kimbrel, and he's since made two All-Star appearances.
16. Joc Pederson, Dodgers, OF (age 23)
Born: Palo Alto, Calif.
HS: Palo Alto (Calif.) HS
Signability concerns led Pederson to fall all the way to the 11th round of the 2010 Draft. The Dodgers scooped him up and gave him a $600,000 bonus that has proven to be well worth it. His power game developed as he climbed the Minor League ladder, and he emerged this year as the Dodgers' everyday center fielder, a leading NL Rookie of the Year Award candidate and the Home Run Derby runner-up. Pederson's dad, Stu, played eight hitless games with the Dodgers in 1985. Suffice it to say Pederson's career is off to a better start.
17. Yasiel Puig, Dodgers, OF (age 24)
Born: Cienfuegos, Cienfuegos, Cuba
After he defected from his native Cuba and established temporary residency in Mexico, Puig was given a seven-year, $42 million contract by the Dodgers in 2012. A year later, he got to the bigs and made an instant impact, earning the nickname "Wild Horse" from Vin Scully because of the risks he'd take on the field. Love or hate him, he's one of the game's few true five-tool talents.
18. Michael Wacha, Cardinals, RHP (age 24)
Born: Iowa City, Iowa
HS: Pleasant Grove HS (Texarkana, Texas)
College: Texas A&M
From the legion of tall, competitive and dominant arms that brought you Chris Carpenter and Adam Wainwright comes Wacha, the latest Cardinal with major mystique on the mound. Just a little more than a year after the Cards took him with the 19th overall pick out of Texas A&M in the 2012 Draft, Wacha took a no-hitter into the eighth inning in the NL Division Series in just his 10th Major League start, and he won NL Championship Series MVP honors. He's been a steady, All-Star-worthy force ever since.
19. Jason Heyward, Cardinals, OF (age 25)
Born: Ridgewood, N.J.
HS: Henry County HS (McDonough, Ga.)
The stories about how Heyward fell to his hometown Braves at No. 14 overall in the 2007 Draft are legendary. Reportedly, former Atlanta scouting director Roy Clark had an agreement with Heyward's high school coach to throw bad batting practice in front of other scouts so that they wouldn't see Heyward at his best. Whatever the tactic, the end result was Heyward winning two Gold Gloves and making an All-Star appearance in five seasons in Atlanta, before his trade to the Cardinals last winter for the player two spots below him on this list.
20. Mookie Betts, Red Sox, OF (age 22)
Born: Nashville, Tenn.
HS: John Overton HS (Nashville, Tenn.)
For all those who strongly felt baseball needed another Mookie, here you go. Actually, though, the first sport this Mookie excelled at was bowling, which he took up when he was just 2. Betts has claimed to have averaged a 225 while rolling five days a week last offseason. But Betts clearly need not pursue a professional bowling career as a fallback option, because his speed, power, athleticism and patience make him a dynamic leadoff threat for the Red Sox.
21. Shelby Miller, Braves, RHP (age 24)
Born: Houston, Texas
HS: Brownwood (Texas) HS
A hard-thrower from rural Texas, Miller was often compared to a young Nolan Ryan when the Cardinals drafted him with the 19th overall pick in 2009. In his rookie season of 2013, he had some Ryan-like flashes of dominance in the first half, though his effectiveness waned a bit in the second and the Cards famously used him for only one inning in the postseason. After a wayward '14, they traded Miller to Atlanta, and the Braves have watched him put together a breakout All-Star season.
22. Carlos Martinez, Cardinals, RHP (age 23)
Born: Puerto Plata, Dominican Republic
It's a good thing Martinez abandoned his initial plans to become a priest, because baseball has worked out wonderfully for him. It's also a good thing that the Cardinals did the necessary investigative work to clear up the confusion about Martinez's birth records that had led to the cancellation of his initial deal with the Red Sox. Martinez had gone by his uncle's last name, Matias, until the death certificate of his birth mother proved his real identity to the U.S. Consulate. The Cards were able to sign Martinez at 18, and now, at 23, he's used his electric stuff to become an All-Star.
23. Eric Hosmer, Royals, 1B (age 25)
Born: South Miami, Fla.
HS: American Heritage School (Plantation, Fla.)
Did you have one of those Tony Gwynn-endorsed Solohitters in your backyard as a kid? Hosmer, the son of a firefighter and a nurse, did, and he'd spend hours hacking at that ball attached to the elastic cord, honing the swing that would earn him a $6 million signing bonus when the Royals drafted him third overall in 2008. Hoz's well-documented promise and potential really came to fruition during the Royals' 2014 AL pennant run, during which he famously bought drinks for everybody in a Kansas City bar to celebrate the team's advancement.
24. Salvador Perez, Royals, C (age 25)
Born: Valencia, Venezuela
Abandoned by his father and raised by his mother and grandmother, Perez was enrolled in a baseball school in his native Venezuela at age six. By age 8, he was convinced his future was at catcher. By 16, the Royals had taken notice and signed him to a $65,000 bonus, and now he's one of the faces of their franchise and one of the best all-around catchers in the game. Perez caught 150 games in the regular season last year, followed that up by catching every game of the Royals' run to the World Series and then participated in the Japan All-Star Series. He simply loves to play, and Kansas City fans love him.
25. Xander Bogaerts, Red Sox, SS (age 22)
Born: Oranjestad, Aruba
HS: Colegio Arubano (AW)
Just the fifth player from Aruba to reach the big leagues (joining Sidney Ponson, Calvin Maduro, Gene Kingsale and Radhames Dykhoff), Bogaerts arrived in 2013 and looked surprisingly comfortable on the October stage, especially for a 20-year-old. He played a big role for the Red Sox in the ALCS win over the Tigers that preceded their World Series title. Now established as the starting shortstop, Bogaerts has made serious offensive strides in 2015.
Also receiving votes: Byron Buxton (Twins), Steven Matz (Mets), Jake Odorizzi (Rays), Joe Panik (Giants), Anthony Rendon (Nationals), Addison Russell (Cubs), Miguel Sano (Twins), Kyle Schwarber (Cubs), Andrelton Simmons (Braves), Noah Syndergaard (Mets), Kolten Wong (Cardinals).
Anthony Castrovince is a reporter for MLB.com. Read his columns and follow him on Twitter at @Castrovince.