At some point this season, the Washington Nationals are going to pencil center fielder Victor Robles in their lineup and leave him there. This will be an important moment for the franchise, because Robles could be one of those special players that comes once a generation or so.(Considering the Nationals

At some point this season, the Washington Nationals are going to pencil center fielder Victor Robles in their lineup and leave him there. This will be an important moment for the franchise, because Robles could be one of those special players that comes once a generation or so.

(Considering the Nationals already have one of those players in Bryce Harper , it happens more than once a generation for some franchises.)

Robles can win games with his bat, glove, legs and arm. He has speed that dazzles and a confidence that's infectious. Did we mention that Robles is just 20 years old? Or that he has played only a handful of games above Class A ball?

Doesn't seem to matter anymore, does it? Robles may eventually be the poster boy for an entire franchise or maybe even a generation of players. For now, though, he's simply part of the next wave of young talent that has reshaped Major League Baseball.

Once upon a time, teams were timid about pushing young players through their system. They relied more on timetables than talent.

Maybe things began to change in 2012, when the Nationals called up Harper and made him an everyday player at 19. He hit .270 that first season and had some good times and some not so good.

But there was never a moment when Harper looked overmatched on his way to making the National League All-Star team five times in six seasons and winning the NL MVP Award in 2015.

Around that time, other teams began to tear up the old player development formulas. They pushed their best prospects, challenged them, trusted their talent more than their age.

Yes, there's an economic component to all of this given that young players are cheaper and controllable for at least six seasons.

Since then, everything has changed. Last season, the All-Star Game had seven players 23 or younger, including 21-year-old Dodgers first baseman Cody Bellinger .

Almost half the 2017 All-Stars (33) were 27 or younger. Overall last season, MLB had 35 position players and 26 pitchers who were 22 years old or younger.

Which brings us to the threshold of another Spring Training, and an opportunity for all 30 teams to get a look at their best prospects. With that in mind, here are 15 to keep an eye on. Among them, all but three ( Ozzie Albies , Rafael Devers and Yoán Moncada ) still have rookie eligibility and ended last season on MLB Pipeline's Top 100 Prospects list. And they'll almost certainly find themselves on the 2018 Top 100 list that will be revealed on MLB Network on Saturday, Jan. 27 at 8 p.m. ET.

Victor Robles, CF, Nationals

Age: 20

2017: .875 OPS, 10 homers, eight triples, 27 steals at Class A/Double-A

The Nationals' outfield is set with Harper, Michael A. Taylor and Adam Eaton , so Robles almost certainly will open the season in the Minors. Harper's impending free agency could open a spot in 2019, but Robles appears to be ready now.

Willie Calhoun , LF, Rangers

Age: 23

2017: .927 OPS, six triples, 31 homers at Triple-A

Calhoun brings speed and power to the table. With him in left and 22-year-old Nomar Mazara in right, the Rangers seem set at the corner outfield spots for the foreseeable future.

Gleyber Torres , 3B/2B, Yankees

Age: 21

2017: .863 OPS at Double-A/Triple-A

The Yankees could have dominated this list with infielder Miguel Andújar and pitchers Chance Adams and Justus Sheffield all expected to play this season. But Torres is the crown jewel of the Yanks' farm system, and he will be one of the most watched players in Spring Training.

Ozzie Albies , 2B, Braves

Age: 21

2017: .810 OPS in 244 MLB plate appearances.

Albies did not disappoint in 57 games for the Braves last season, and he is one of the reasons Atlanta's future is so bright. (And, of course, there is also Ronald Acuna, Albies' teammates in Atlanta. He might be the most hyped youngster in baseball this side of Shohei Ohtani and doesn't need much more pub from me.)

Rafael Devers, 3B, Red Sox

Age: 21

2017: .819 OPS in 240 MLB plate appearances

The Red Sox shopped for a veteran third baseman before becoming convinced Devers was their best option. He debuted at 20 in July and did almost everything well.

Yoan Moncada, 2B, White Sox

Age: 22

2017: .750 OPS, eight homers in 231 MLB plate appearances

Moncada struggled some in 54 games, but his skillset and Minor League resume are so solid that he's almost certain to be a cornerstone for the South Siders' rebuild.

Jack Flaherty , RHP, Cardinals

Age: 22

2017: 8.9 K/9, 1.043 WHIP at Double-A/Triple-A

Flaherty has gotten consistently better during 72 Minor League starts, and he has developable four other serviceable pitches to go with a 95-mph fastball. The Cardinals have smartly resisted any temptation to deal him for a closer or third baseman.

A.J. Puk , LHP, A's

Age: 22

2017: 13.2 K/9, 1.248 WHIP at Class A/Double-A

Puk made 13 starts at Double-A last season, and he is on the fast track to make his Oakland debut sometime this season. The A's are getting better quickly, and Puk is one of the reasons.

Walker Buehler , RHP, Dodgers

Age: 23

2017: 12.7 K/9, 1.11 WHIP at Class A/Double-A/Triple-A

Buehler's Twitter handle is @buehlersdayoff, and please don't tell me you have to look it up. He has three power pitches and will have his workload carefully monitored after throwing 98 innings last season in his return from Tommy John surgery.

Vladimir Guerrero Jr., INF, and Bo Bichette, INF, Blue Jays

Age: Guerrero is 18, Bichette is 19

2017: Guerrero .910 OPS at Class A; Bichette .988 OPS at Class A

Neither is likely to play in the Majors this season, although stranger things have happened. Instead, they're two reasons Blue Jays fans should be optimistic about the future.

Jorge Alfaro , C, Phillies

Age: 24

2017: .874 OPS in 114 MLB plate appearances

Alfaro was the cornerstone of the trade that sent Cole Hamels to the Rangers, and he is part of the foundation the Phillies are constructing. Power arm and power bat.

Brent Honeywell , RHP, Rays

Age: 22

2017: 11.3 K/9, 1.24 WHIP at Double-A/Triple-A

Honeywell's fastball touches 95 mph at times, and he has four other big league-ready pitches. But it's his changeup -- a screwball -- that generates a high number of swings and misses.

Forrest Whitley, RHP, and Kyle Tucker, OF, Astros

Age: Whitley 20, Tucker 21

2017: Whitley 13.9 K/9 at Class A/Double-A; Tucker .874 OPS, 25 HR at Class A/Double-A

GM Jeff Luhnow made both of these guys untouchable, and Houston could get nice contributions from both in 2018. Neither will open the season in the big leagues, but both give the Astros nice depth.