Baseball has witnessed a proliferation of home run-hitting rookies in recent years.
In 2016, Gary Sanchez became the first player to homer 18 times in his first 45 games, only to see that record obliterated when Rhys Hoskins went deep 19 times in his first 34 games the next season. Overshadowing Hoskins in 2017, Aaron Judge (52) and Cody Bellinger (39) each set league records for long balls by a rookie. This year, Ronald Acuna became the youngest player (age 20) known to have homered in five straight games and seven of eight, finishing the season with 26, while Juan Soto slammed the second-most homers ever by a teenager (22).
Who will form the next wave of young sluggers? Below, we identify the top power-hitting prospect in each organization, focusing on usable power (translatable into home run production) as opposed to simply raw power.
AL East
Vladimir Guerrero Jr., 3B, Blue Jays No. 1 (MLB No. 1)
The 19-year-old phenom is the best hitter in the Minor Leagues, and it's not even close. The truly amazing part, however, is that he hasn't even begun in earnest to tap into the enormous raw power he's shown flashes of at times in his career -- which says a lot considering he totaled 20 home runs and 26 doubles in 91 games while also hitting .381(!) this season between Double- and Triple-A.

MILB Video - Title: Watch: Vlad Jr. crushes 2-run shot - Url: http://www.milb.com/r/video?content_id=2434066983

Ryan Mountcastle, 3B, Orioles No. 2 (MLB No. 63)
Mountcastle hit 13 home runs in Double-A this year after going deep 18 times and leading the Minors with 48 doubles in 2017. Much of that had to do with the fractured right hand that sidelined him until mid-May, as Mountcastle still showed plenty of raw power to the big part of the field as he has throughout his career. Because of a swing that features natural loft and remains in the zone for an extended period of time, it's easy to envision many of Mountcastle's doubles clearing the fence in future seasons.
Nate Lowe, 1B, Rays No. 13
One of the top breakout prospects of 2018, Lowe, a 13th-round pick in the 2016 Draft, produced a .330/.416/.568 line with an organizational-best 27 home runs as well as 32 doubles while ascending from Class A Advanced Charlotte to Triple-A Durham. With power that plays to all parts of the field, the 23-year-old first baseman could soon be hitting in the middle of Tampa Bay's big league lineup.
Bobby Dalbec, 3B, Red Sox No. 6
Dalbec bounced back from a hamate injury that ruined his first full pro season in 2017 to rank fourth in the Minors with 32 homers this season, as well as place second with 70 extra-base hits and 109 RBIs. A fourth-round pick from Arizona in 2016, Dalbec comes with swing-and-miss concerns, but his raw power has prompted comparisons to Kristopher Bryant.
Estevan Florial, OF, Yankees No. 2 (MLB No. 45)
Florial's bat speed and the loft in his left-handed swing give him plenty of raw power, though he's still figuring things out at the plate and homered just six times in 84 games while dealing with a hamate injury. Signed out of Haiti in 2015, he has two more well above-average tools in his speed and arm strength.
AL Central
Bobby Bradley, 1B, Indians No. 7
The 22-year-old left-handed slugger connected on 27 home runs between Double- and Triple-A and has now totaled at least 23 long balls in each of his first four full seasons. Bradley's massive raw power comes paired with strikeout concerns as well as some inherent streakiness, but he also has a sound approach that portends even more consistent game power down the road.
Seuly Matias, OF, Royals No. 3
Matias' season came to a premature end when he severely cut his right thumb on the cargo door of the team bus while loading his luggage in mid-August, but he still led the Minors in homers per plate appearance (one every 12.1) and ranked sixth with 31 homers in just 94 games. Signed for $2.25 million out of the Dominican Republic in 2015, he also homered at the SiriusXM All-Star Futures Game, where World manager David Ortiz likened him to a young Sammy Sosa.
Christin Stewart, OF, Tigers No. 6
He's led the Tigers organization in home runs in each of his three full seasons of pro ball, with at least 25 in each season and a high of 30 in 2016, his first full year after coming out of Tennessee. He improved his overall approach without sacrificing power in 2018, cutting his K rate but still hitting 25 long balls.
Brent Rooker, 1B, Twins No. 7
Rooker showed how advanced his bat is by reaching the Florida State League and hitting 18 homers in 62 games during his summer pro debut in 2017. He went straight to Double-A in 2018 and led the Twins with 22 home runs, 13 of which came during a torrid June and July.
Eloy Jimenez, OF, White Sox No. 1 (MLB No. 3)
The jewel of the White Sox's 2017 trade that sent Jose Quintana to the Cubs, Jimenez is the closest rival to Blue Jays third baseman Vladimir Guerrero Jr. as the best offensive prospect in baseball. The Dominican battled pectoral and adductor strains in 2018 yet still set career highs in homers (22) and slugging (.577) while dominating Triple-A at age 21.

MILB Video - Title: Watch: MiLB Video - Url: http://www.milb.com/r/video?content_id=2446893883

AL West
Jo Adell, OF, Angels No. 1 (MLB No. 15)
His raw power has been on display since his high school days, when he hit 25 homers as a senior. Given some questions about his swing-and-miss tendencies, no one would have predicted he'd get to Double-A in his first full season of pro ball. He hit 20 homers in just 99 games along the way for a .543 slugging percentage.
Kyle Tucker, OF, Astros No. 1 (MLB No. 5)
Three picks after taking Alex Bregman with the No. 2 overall pick in the 2015 Draft, the Astros grabbed Tucker, who has a similarly lofty offensive ceiling. He led the Triple-A Pacific Coast League in slugging (.590) and OPS (.989) while recording his second straight 20-20 season.

MILB Video - Title: Watch: Tucker's game-tying homer - Url: http://www.milb.com/r/video?content_id=2488574983

Lazaro Armenteros, OF, Athletics No. 6
Lazarito's eight home runs in 79 games at Class A Beloit as a 19-year-old this past season don't accurately reflect his power potential. The Cuban product has a chiseled frame at 6 feet and182 pounds and already shows feel to hit, leading scouts to project him for a considerable uptick in power as he continues to develop and become better acclimated to pro ball.
Kyle Lewis, OF, Mariners No. 1
Lingering effects from the severe knee injury Lewis suffered during his pro debut have kept him from making a true impact in either of his first two full-season campaigns. As a result, it's still easy to dream of the 2016 first-rounder eventually tapping the raw power he's long shown glimpses of. Joey Curletta was also considered after the 24-year-old first baseman went deep 23 times en route to Double-A Texas League Player of the Year honors.
Anderson Tejeda, SS, Rangers No. 10
Tejeda immediately began impressing scouts with his power when he made his U.S. debut in 2016, two years after signing out of the Dominican Republic, and launched 28 extra-base hits in 55 games. He continues to display uncommon pop for a middle infielder, ranking sixth in the high Class A Carolina League with 19 homers this season as one of its younger regulars (age 20).
NL East
Austin Riley, 3B, Braves No. 5 (MLB No. 43)
Riley's raw power has always been a known commodity. What's surprised some is how good he's been at making adjustments at the plate so he can consistently tap into it. He's hit 59 homers the past three seasons combined and despite missing time with injury, he posted a career high (for a full season) with his .522 SLG.

MILB Video - Title: Watch: Riley cranks solo homer - Url: http://www.milb.com/r/video?content_id=2451787183

Monte Harrison, OF, Marlins No. 2
The 6-foot-3, 220-pounder's power has blossomed in the last two seasons in the form of 21- and 19-homer campaigns, though it's come at the cost of a soaring strikeout rate and perpetuated concerns about his contact skills. At the same time, it's important to remember that the 23-year-old outfielder is still playing catch-up developmentally after a decorated multi-sport prep career followed by an injury-plagued start to his pro career.
Peter Alonso, 1B, Mets No. 2 (MLB No. 58)
Not only did Alonso tie for the Minor League lead with 36 homers (and lead the Minors outright with 119 RBIs), he's shown ridiculous exit velocity with home runs on big stages (113.6 mph at the Futures Game; 110 mph at the AFL's Fall Stars Game). Each blast knocks louder on the big league door.
Carter Kieboom, SS, Nationals No. 2 (MLB No. 37)
The 2016 first-rounder impressed with his power potential in his first fully healthy season, connecting on 16 homers and 31 doubles in 123 games while reaching Double-A. Kieboom's uptick in power didn't detract from his hitting ability or approach either -- a big reason why evaluators forecast the 21-year-old shortstop to find even more power as he adjusts to upper-level pitching.
Darick Hall, 1B, Phillies
For two years running, the big first baseman has led the organization in homers (tying with Hoskins in 2017) and RBIs. He's hit 54 homers over those two seasons, reaching Double-A for the first time in 2018. An improved approach should let him tap into his power even more.
NL Central
Keston Hiura, 2B, Brewers No. 1 (MLB No. 30)
You'd be hard-pressed to find a right-handed hitter with a more impactful right-handed swing and better bat-to-ball skills than Hiura, who slashed .293/.357/.464 with 52 extra-base hits in his first full season. Corey Ray and Jake Gatewood also have impressive power, however Hiura's consistent stroke and feel for using the big part of the field make him a better candidate to apply his power all the way up the ladder.

MILB Video - Title: Watch: Hiura's 3-run blast - Url: http://www.milb.com/r/video?content_id=2477977883

Nolan Gorman, 3B, Cardinals No. 2 (MLB No. 73)
All Gorman did was lead all 2018 draftees with 17 homers in 63 total games that led to a .570 SLG and .950 OPS in his pro debut. The No. 19 overall pick out of the Arizona high school ranks was so impressive, he reached full-season ball and silenced some who worried about how his hit tool would play in pro ball.
Nelson Velazquez, OF, Cubs No. 21
Though Velazquez wasn't ready for full-season ball in his first full pro season, he still has the best power potential in the Cubs system and hinted at it by slugging .458 in the short-season Northwest League. A fifth-round pick as a Puerto Rico high schooler in 2017, he has a quick right-handed bat and a take-no-prisoners approach.
Oneil Cruz, SS, Pirates No. 4
Others hit more home runs than he did in the Pirates system in 2018 (Will Craig topped it with 20), but the 6-foot-6 shortstop took a big step forward overall offensively and did hit 14 out as a teenager in the South Atlantic League. There is no question there's much more pop to come as he fills out that frame.
Ibandel Isabel, 1B, Reds
Isabel's power started showing up big time in 2016 when he slugged .579 and reached full-season ball with the Dodgers. He followed that up with a 28-homer breakout in 2017. The Reds acquired him last April and he finished with 36 home runs, tying for the Minor League lead, and has a career .513 SLG.
NL West
Kristian Robinson, OF, D-backs No. 12
He has a long way to go as a 17-year-old with just 222 career at-bats on his professional resume. But people talk about his raw power in hushed tones and it was on display during instructs more consistently. As he fills out his 6-foot-3 frame, his .428 slugging percentage will assuredly increase.
DJ Peters, OF, Dodgers No. 8
Peters has a long track record of power production, setting a Western Nevada CC home run record (16) in the program's final season in 2016; leading the Rookie-level Pioneer League in total bases (161) and OPS (1.052) in his pro debut that summer; topping the high Class A California League in extra-base hits (61) and slugging (.514) en route to MVP honors in 2017; and pacing the Double-A Texas League in homers (29), extra-base hits (55) and total bases (232) this summer. He derives his pop from impressive strength and leverage in his 6-foot-6 frame.
Chris Shaw, OF, Giants No. 4
The best college power hitter available in the 2015 Draft, Shaw led the Cape Cod League with eight homers the previous summer and the short-season Northwest League with 12 in his pro debut. The Boston College first-rounder has since mashed 69 homers in three full Minor League seasons, then smoked a Seunghwan Oh slider 468 feet for his first big league blast in September.
Fernando Tatis Jr., SS, Padres No. 1 (MLB No. 2)
He became the first 18-year-old in Midwest League history to post at least 20 home runs and 20 stolen bases in 2017, and would have posted another 20-20 season in Double-A at age 19 this past season if not for a season-ending thumb injury in late July. Tatis has already shown in-game power to all fields and has massive raw power to his pull side.

MILB Video - Title: Watch: Tatis crushes leadoff homer - Url: http://www.milb.com/r/video?content_id=2286614383

Brendan Rodgers, INF, Rockies No. 1 (MLB No. 9)
The No. 3 overall pick in the 2015 Draft, Rodgers looks like the heir apparent to DJ LeMahieu at second base in Colorado. He has a knack for barreling balls and making loud contact, which has resulted in 57 homers and a .491 slugging percentage in 350 pro games.