Like the seasons of the year or the phases of the Marvel Cinematic Universe, prospect classes in baseball have visible, definable endpoints. For the hyper-talented rookie group of 2019, you could put a date on the end of its cycle: May 3. That’s when the Reds called up Nick Senzel, the No. 2 pick in the 2016 draft, making him the latest and perhaps last of an impressive freshman cohort that includes Vladimir Guerrero Jr., Fernando Tatis Jr., Pete Alonso, Eloy Jimenez, Victor Robles, and Chris Paddack.

Just 23 years old, Senzel—a third baseman in college but an outfielder in the big leagues—ranked in the top 10 of the preseason top 100 lists of Baseball America, Baseball Prospectus, MLB.com, and FanGraphs. So, too, did Tatis Jr., Jimenez, and Robles (except for MLB’s list, which he graduated off of this winter, and BA, where he just missed at No. 11), while Guerrero reigned as the No. 1 on all four. They were not just the cream of this year’s crop, but also those closest to making a major league impact.

With Senzel joining his fellow top prospects in the majors, then, it’s time to refocus on who’s coming next. It’s worth remembering that some of these players will get hurt or never reach their potential. Nor will they all have an immediate impact if they make it to the majors. Look no further than Guerrero, who annihilated minor league pitching over the last three-plus seasons but has struggled with his first taste of the bigs. No matter how talented they are, they can’t solve the sport overnight. No one can.

Regardless, these are the names to keep an eye on for the summer and into the fall—and in some cases, maybe to see sometime toward the end of the season, joining the likes of Guerrero, Tatis, Alonso, Senzel and the rest. The Class of 2019 may not be done quite yet.

The preseason rankings below are pulled from Baseball America, Baseball Prospectus, MLB.com, and FanGraphs.

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Wander Franco, SS, Rays

Preseason Rankings: BP: 10 | BA: 4 | MLB: 12 | FG: 2

Just 18 years old, Franco—the top player in his international signing class back in 2017—rocketed up prospect lists after clobbering the Appalachian League in rookie ball last year, hitting .351/.418/.587 with 11 homers. FanGraphs, the highest on his potential this winter, wrote, “Franco is about as close as you’ll see to a perfect prospect at this point,” throwing plus grades on his power, speed and defense. It’s an exciting development for the Rays, but given his age and current league (low A ball), he’s still a while away from making an impact in Tampa.

Casey Mize, RHP, Tigers

Preseason Rankings: BP: 36 | BA: 16 | MLB: 16 | FG: 30

The No. 1 pick of the 2018 draft, the big righty out of Auburn will be in the conversation for the No. 1 prospect in baseball midseason after his brilliant start to the year. Mize completely dominated his competition in high A ball, striking out 25 and allowing just one run in 26 innings, and when given a much tougher assignment in Double A, he responded by throwing a no-hitter in his first start at the level. “With plus command and the ability to induce whiffs with three different pitches, Mize has the ingredients needed to headline a starting rotation,” notes MLB.com’s write-up. So far, those ingredients have come together quite nicely, and if he keeps it up, a September cup of coffee in Detroit isn’t out of the question.

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Forrest Whitley, RHP, Astros

Preseason Rankings: BP: 7 | BA: 5 | MLB: 6 | FG: 4

Then again, Mize may not even be the best pitcher on this list, given Whitley’s drool-inducing stuff. A first-round pick out of a San Antonio high school in 2017, the righty is built like a skyscraper at 6’7” and is coming off a 2018 in which he punched out 34 in 26 1/3 innings at Double A before also crushing the competition at Arizona Fall League. The knock here is a 50-game PED suspension that cost him most of last season, and his 2019 campaign in Triple A has been a mess so far (22 runs allowed in 18 1/3 innings). But his 98-mph fastball and bevy of plus offspeed and breaking pitches give him ace upside, as well as a real chance, if he can straighten things out, to earn a rotation spot in Houston near midseason.

MacKenzie Gore, LHP, Padres

Preseason Rankings: BP: 28 | BA: 27 | MLB: 14 | FG: 22

It’s practically unfair that a San Diego team already boasting Tatis Jr., Paddack, Franmil Reyes, and Francisco Mejia should have even more All-Star-caliber talent under 25 waiting in the wings. But the rich will get richer once Gore arrives, though given that he’s only 20 and in high A, that won’t be for a while longer. Or maybe not: He’s currently destroying that level, with 52 strikeouts and just five runs allowed in 37 innings. That’s thanks to four plus pitches: a fastball that sits 93–95 mph, a knee-buckling curveball, a hard slider, and a dancing changeup. He has all the tools to give the Padres yet another young star—you know, as if they needed one. (He's also already been on the cover of SI)

Nolan Gorman, 3B, Cardinals

Preseason Rankings: BP: 34 | BA: 75 | MLB: 55 | FG: 85

The heir apparent to Matt Carpenter at the hot corner in St. Louis, Gorman was the team’s first-round pick last summer out of a Phoenix high school, so he’s still got some maturing to do in the minors. Nonetheless, the 19-year-old was stellar in 2018, hitting .291/.380/.570 across two levels, and he’s kept it up this year, slashing .254/.367/.556 against older competition in low A. Boasting tons of raw power—FanGraphs gave him a 70 grade, MLB a 60 on that tool—Gorman has the potential to be a middle-of-the-order fixture for the Cardinals.