Some players are on the verge of stardom, others are entering a crucial phase of their development and still others are getting their first tastes of full-season ball. With the 2019 season approaching, MiLB.com takes a look at the most intriguing prospects from each MLB organization.
Shining star: Sixto Sanchez, RHP
The prospect returns the Marlins received after trading away All-Star outfielders Giancarlo Stanton, Christian Yelich and Marcell Ozuna last offseason could be viewed as underwhelming to this point, but in acquiring Sanchez from the Phillies for J.T. Realmuto, Miami may have received the real deal: an ace-level future starter.
The 20-year-old easily reaches the upper 90s with tremendous movement on his fastball and possesses a plus curveball and changeup as well. He has incredible command -- the Dominican native owns a 0.99 WHIP in 221 1/3 career Minor League innings -- and his sinking two-seamer helps keep the ball in the park: He's yielded just three home runs as a pro.
"What we've seen is fantastic," Marlins director of player development Dick Scott told MLB.com. "The ball comes out well and there's a lot of life to his arm. He's a great kid and we've really liked the early glimpses we've seen."
The main question surrounding Sanchez is his durability. At six feet and 185 pounds, he is small for a power pitcher, and he has never pitched more than 95 innings in a season. In 2018 he was limited to 46 2/3 frames by elbow inflammation and collarbone soreness. If he has a healthy 2019 campaign, he could be ready to join the Marlins rotation as soon as next season.
Full-season debutant: Victor Victor Mesa, CF
Signed for $5.25 million in October, Mesa (along with his younger brother Victor Jr., who also signed with the Marlins) is the son of legendary Cuban outfielder Victor "El Loco" Mesa. Victor Victor debuted in Cuba's top domestic league at 16 and went 3-for-7 as a 20-year-old in the 2017 World Baseball Classic. Now 22, the speedy outfielder is ready to make his stateside debut -- likely with Double-A Jacksonville -- although a hamstring injury suffered early in Spring Training has limited his playing time.
"He's got speed. He can fly in the outfield," Gary Denbo, Miami's vice president of player development and scouting, told MLB.com. "His defensive abilities are very good. His throwing arm is very good. We think he's going to hit for a high average. What remains to be seen is if he hits for power or not."
Mesa's best home run total in the Cuban National Series was seven, in 70 games, for Matanzas in 2016-2017. (He struck out just 19 times in that campaign while drawing 17 walks and stealing 40 bases.) Developing power will be a key this season for Mesa, who appears to have all the other tools to thrive in the Majors.
Back and healthy: Braxton Garrett, LHP
The seventh overall pick (out of high school in Alabama) in the 2016 Draft, Garrett pitched just 15 1/3 innings as a pro before undergoing elbow surgery in June 2017. Now 21, the left-hander is trying to get back to the form that earned him a $4.1 million signing bonus.
Before his injury, Garrett featured a low-90s fastball, excellent curve and solid changeup. He still has mid-rotation potential but remains a question mark after three pro seasons in which he barely pitched. 2019 will be a new beginning for Garrett as he stretches out his rebuilt arm and faces professional hitters for an extended time.
At the crossroads: Monte Harrison, CF
Of all the players featured in our 30 Prospect Primers this spring, Harrison may be the best pure athlete. At 6-foot-3 and 220 pounds, the outfielder has a cannon arm along with tremendous power -- according to Marlins metrics, 20 percent of the balls he put in play in Double-A had exit speeds of more than 105 mph, nearly three times the MLB average of 7 percent -- and speed (he stole 28 bases for Double-A Jacksonville in 2018).
Video: Jacksonville's Harrison hits no-doubter
For Harrison, the ongoing problem is making contact. Last year he struck out in an astonishing 36.9 percent of his plate appearances and led the Minor Leagues with 215 K's in 136 games. (Only four Major Leaguers exceeded a 30 percent strikeout rate in 2018.) Without a significant bump in home runs -- he hit 19 for the Jumbo Shrimp last season -- those strikeout numbers are a huge drag on his effectiveness and viability as a Major Leaguer. Harrison eliminated his leg kick while playing in the Arizona Fall League last year and cut his strikeout rate to 25 percent in 19 games, but also went homerless. Finding a happy medium between his current all-or-nothing approach will be a key for him this year in his age-23 season.
"Monte is an unbelievable athlete," Scott said. "He can run, throw, hit, hit for power. He can play defense in the Major Leagues right now. It just hasn't all come together for him yet.
"He made huge adjustments with his stance and approach in the Fall League. He got away from his big leg kick, changed where he held his hands and stayed in the middle of the field more. It was pretty bold by him and it worked out."
Loudest tool: RHP Jorge Guzman
Signed by the Astros in 2013 and acquired by the Yankees in the Brian McCann deal before being sent to Miami in the Stanton trade last winter, Guzman owns a fastball that MLB.com has graded 80 on the 20-to-80 scale. The right-hander has reached 103 mph with it and sits between 95 and 98. In his first season with the Marlins last year, Guzman fanned 101 batters over 96 innings but also walked 64 -- a jump from 2.43 walks per nine innings in 2017 to 6.00 in the Florida State League.
There's no doubting the radar gun or the demand for velocity in the Majors, but whether he remains a candidate for the rotation or heads to the bullpen will depend on rediscovering his command. As the 23-year-old moves up the ladder, sheer velocity won't be enough to cow experienced hitters.
Others to keep an eye on: Catcher Will Banfield, a supplemental second-round pick out of high school last June, has the arm, elite defensive skills and makeup to rise quickly -- if his bat can keep pace. ... Righty Jordan Holloway was a 20th-round pick in 2014 but is still only 22. After undergoing Tommy John surgery in 2017, he's looking to reestablish his plus fastball and curve while developing needed control in his first full season back. ... LHP Will Stewart is another 20th-round pick, but otherwise quite different from Holloway. Acquired from Philadelphia in the Realmuto trade last month, the 21-year-old Stewart is more in the "crafty lefty" mold -- he won't overpower hitters, but the strong sinking action on his fastball helps him generate weak contact and keep the ball in the park.
2019 organization predictions:
Most home runs: Harrison
Most stolen bases: Brian Miller
Most strikeouts: Sanchez
Current prospect to get most Major League playing time: Nick Neidert
Non-Top 100 prospect to end 2019 in the Top 100: Garrett