Top MLB Prospects At The 2018 Arizona Fall League
Even before the rosters for the Arizona Fall League teams were released in late August, there was already a buzz about the quality of the prospects that would be coming to the southwest desert in the fall. Long-term observers consider the 2018 class to be one of the strongest in the league’s 27-year history, even considering that blue chippers like Bo Bichette (Blue Jays), Sixto Sanchez (Phillies), Brent Rooker (Twins) and Michael Chavis (Red Sox) were scratched from their respective rosters.
To qualify for this list, hitters must have recorded at least one plate appearance per their team’s game played, and pitchers must have completed at least one inning for every three team games.
1. Vladimir Guerrero Jr., 3B, Surprise (Blue Jays)
For the third straight year, a 19-year-old position player from Latin America ranks as the top prospect in the Arizona Fall League, with Guerrero Jr. following in the footsteps of Gleyber Torres (Yankees, 2016) and Ronald Acuna Jr. (Braves, 2017). There’s not much left to say about Baseball America’s No. 1 overall prospect that hasn’t already been said multiple times, as he earns a 80-grade on his ability to hit and a 70-grade on his future power.
Guerrero kept his batting average near the .500 mark for the first half of the six-week AFL season before tiring over the final three weeks. In the end, he still put up an impressive .351/.409/.442 slash line. The only concerns about Guerrero’s future is his already husky body and whether or not he’ll be able to stay at third base long-term. His feet move well at the hot corner and he has a plus arm, but his size may push him across the infield at some point. Regardless, Guerrero is going to be an elite hitter for many years to come.
2. Forrest Whitley, RHP, Scottsdale (Astros)
Whitley came into the Arizona Fall League as baseball’s top pitching prospect, and the 21-year-old righthander didn’t disappoint. Whitley was making up for lost time from the regular season, when he made only eight starts at the Double-A level due to a 50-game suspension for violating minor league baseball’s drug policy and then a strained right oblique injury.
Starting his AFL season with a bang, Whitley struck out eight of the first nine batters he faced in his Opening Night start. He finished the six-week season with a 2.42 ERA, a .189 opponent average and a 36-to-7 strikeout-to-walk ratio over 26 innings. Typically sitting 94-97 mph with his fastball, Whitley touched 100 mph in the annual Fall Stars Game. According to Whitley, it was the first time he’d hit triple digits with his fastball since high school, and he mixed in the rest of his five-pitch repertoire during his six AFL games.
3. Cristian Pache, OF, Peoria (Braves)
After sending Ronald Acuna Jr. to the Arizona Fall League a season ago, the Braves gave AFL fans another intriguing outfielder to watch this year with Pache, who just turned 20 years old. The Dominican native may not have the upside of Acuna, but he earned plus-plus grades for both his defense and speed and could be an 80-grade defender by the time he hits Atlanta.
Pache still has work to do when it comes to developing his hit tool, but scouts believe he’ll get stronger and grow into 20-plus home run power in time. He’s still a couple of years away from making it to the big leagues, but those who believe in Pache see All-Star potential.
4. Jazz Chisholm, SS, Salt River (D-backs)
Chisholm placed himself firmly on the prospect radar with a strong year split between low Class A Kane County and high Class A Visalia. As a taxi-squad player limited to playing only on certain days, Chisholm didn’t get a lot of game action for Salt River, but he certainly made the most of his 10 games on the field, raising his stock even higher. Chisholm hit an eye-popping .442/.489/.767 with three home runs in 43 at-bats, at times flashing spectacular defense at shortstop.
The key to Chisholm’s improvement has been added strength and the ability to tap into his power more often. He’s a plus defender now, but like most young shortstops he still occasionally misses on some of the easier plays. With a big personality and perpetually engaging smile on the field, Chisholm may soon join Phoenix Suns rookie center Deandre Ayton as the two most popular Bahamian athletes in town.
5. Keston Hiura, 2B, Peoria (Brewers)
One of the top bats in the 2017 draft, Hiura made it to the AFL at the end of his first full professional season, and his outstanding fall earned him the league’s MVP award. Hiura led all hitters with 33 RBIs, posting a .323/.371/.563 slash line with five home runs while showing improved defense at second base for the AFL champion Peoria Javelinas.
Hiura stands out for his feel for the barrel and his potential plus power. There’s still a lot of swing-and-miss concerns, as he fanned 28 times in 96 at-bats, and it’s a pull-heavy approach, but the swing works and he usually stays short to the ball. After an elbow injury in college that limited him to a DH role early in his pro career, Hiura should be an average defender at second base in time. He makes up for a below-average arm with accuracy and a quick release.
6. Luis Robert, OF, Glendale (White Sox)
The most frequent statement made about Robert this fall is that he looks the part, and it could be argued that the Cuba native was the best athlete in the AFL. Making up for lost time due to various injuries during his pro debut in the White Sox organization, Robert hit .324/.367/.432 in 74 at-bats, with one of his two home runs being arguably the most impressive long ball hit by any AFL hitter this season.
At the plate, Robert has strong hands and quick stroke, with the ball coming off his bat well. A plus-plus runner, Robert was successful on all five of his stolen base attempts. With only one partial professional season on his record, the 21-year-old Robert has a lot of development ahead of him but with a wealth of tools to dream on.
7. Taylor Trammell, OF, Scottsdale (Reds)
Trammell might rival fellow outfielder Luis Robert when it comes to raw athleticism, garnering plenty of support from scouts for his ranking among the league’s top prospects. Coming out of the high Class A Florida State League in his third pro season, Trammell wasn’t overmatched by the more advanced pitchers in Arizona, as he posted a .298/.359/.393 slash line.
While he didn’t hit any balls out of the park this fall, Trammell projects to possess an electric power-speed combo at the next level. He’s quick with the bat, although his swing needs to be a little shorter in order to stop pitches from getting too deep in the zone. Trammell primarily played in left field for the Scorpions, with scouts wishing he would have gotten some time in center field during his AFL stint. His plus-plus speed allows him to get to plenty of balls in the outfield, but a below-average arm will keep him out of right field.
8. Carter Kieboom, 2B/SS, Salt River (Nationals)
The Kieboom name was certainly familiar to die-hard AFL fans as older brother Spencer, also a Nationals farmhand, previously spent two seasons in the Arizona Fall League. While some observers were lukewarm on the younger Kieboom early in the fall, he’s the kind of pure ballplayer that takes time to grow on you. Splitting time between both middle infield positions for Salt River, Kieboom hit a solid .295/.427/.372 for the Rafters while drawing 17 walks.
The type of player who will consistently play above his tools, Kieboom has a good feel for hitting and a selective approach at the plate. AFL scouts are mixed as to whether he stays at shortstop or is better suited for second base, but he’s an instinctual defender who projects to be at least an average defender at shortstop.
9. J.B. Bukauskas, RHP, Scottsdale (Astros)
Bukauskas’ starts typically came two days after Forrest Whitley took the hill for the Scorpions, so scouts were able to plan their weekly schedule to regularly catch both of the Astros righthanders. Houston’s first-round pick in 2017, Bukauskas missed time during the regular season due to a back issue and made only 14 regular season starts. He made up for lost time in the AFL with six more appearances, posting a 3.33 ERA and 24 strikeouts in 24.1 innings.
There’s some reliever risk with Bukauskas because of his max-effort mechanics, but both his fastball and slider are plus pitches. He throws a heavy ball and gets deception from his 95-98 mph fastball, hiding it well before it jumps on opposing hitters.
10. Jon Duplantier, RHP, Salt River (D-backs)
Duplantier was assigned to the Arizona Fall League to make up for missing nearly two months to right biceps tendinitis earlier in the season. Earning AFL pitcher of the week honors for the first week of November, Duplantier started six games, posting a 3.32 ERA with an impressive 32 strikeouts in 21.2 innings.
Duplantier’s fastball velocity jumped up a couple of ticks from the regular season, sitting 94-96 mph in the fall, and he mixes in both a slider and a power curveball. In one of his later starts, his nine strikeouts were the second highest total in an AFL game in the last 10 years. With a strong finish to the fall season, Duplantier will be looked at very seriously next spring as a candidate for a potentially rebuilt D-backs rotation.
11. Nate Pearson, RHP, Surprise (Blue Jays)
The last time AFL observers were treated to such consistently high velocity was in 2011, when Aroldis Chapman was a member of the Phoenix Desert Dogs. Pearson regularly hit triple digits, with the highlight being the multiple 103-104 mph fastballs he threw during his one-inning appearance in the Fall Stars Game. His six AFL starts were split between three quality outings and three sub-par performances, but he finished strong by not giving up a run over his last nine innings.
Pearson pitched in only one game during the regular season due to injury, so he certainly needed the work this fall. Toronto’s 2017 first-round pick has a massive 6-foot-6, 245-pound frame, and needs to smooth out a delivery that’s not real free and clean. While he got strikeouts with his mid-70s curveball, it’s still an inconsistent pitch. Pearson likely profiles better as a power reliever at the back end of the bullpen, but with velocity like this he’ll get plenty of time to develop control and harness his stuff.
12. Peter Alonso, 1B, Scottsdale (Mets)
Alonso likely made more social media highlight reels than any other AFL player this season, with his massive home runs and extreme exit velocities taking center stage. Tying for the league lead with six home runs—plus one more long ball in the Fall Stars Game off a Nate Pearson 100-plus mph fastball—Alonso put up decent overall numbers with a .255/.339/.510 slash line. He is not real athletic but is plenty strong, with one observer stating that Alonso has a "blacksmith’s body.”
While not hitting for a high average in the fall and showing troubles with outside pitches and solid breaking balls, Alonso still has feel to hit and manipulates the barrel well. He’s not just a dead-pull hitter, with a couple of his home runs going to right field or right-center field. Alonso is not a great defender, but scouts noted that it can be playable with plenty of hard work.
Stephen Strasburg Signing Opens Path For Carter Kieboom
With Strasburg's signing seemingly dimming the chances of an Anthony Rendon return, a clear path opens for Kieboom.
AFL Prospects On The Rise
The Arizona Fall League provides an excellent opportunity for players to increase their prospect status and their odds of earning a spot on their organization’s 40-man roster. The players listed in this section are not necessarily the next eight top prospects, but rather a sampling of players who used the AFL season to boost their prospect stock.
Nico Hoerner, SS, Mesa (Cubs) — Hoerner was a rarity in the AFL this year as a player assigned to the league in his draft year after only 14 professional games. The Cubs first-rounder was anything but overmatched, as Hoerner showed feel to hit along with good all-around defensive skills.
Tyler Nevin, 3B/1B, Salt River (Rockies) — Coming off a season at the high Class A level, Nevin certainly raised his stock by leading the AFL in most batting categories. The son of ex-big leaguer Phil Nevin showed he can handle better pitching, finding the barrel more and generate good bat speed without pulling off on his swing.
Yu Chang, 3B, Glendale (Indians) — Scouts and AFL coaches agreed that Chang’s bat is ready for a move to the major leagues, except that he’s blocked in Cleveland by Jose Ramirez. The Taiwan native consistently took good at-bats with doubles power to the gap, drawing a comparison to veteran big leaguer Martin Prado. Chang spent time at third base, shortstop and second base during his regular season with Triple-A Columbus, so he could get his first chance with the Indians in a utility role.
Melvin Adon, RHP, Scottsdale (Giants) — Every year there’s an AFL reliever who has scouts peering down to the bullpen to see who’s coming in next while warming up their radar guns. Adon was this year’s fireballing bullpen ace who consistently came in throwing gas, usually touching triple digits with his big frame and live arm. Adon threw more strikes this year and was more consistent with his slider. That improvement is substantiated by the fact that he struck out 21 batters and walked only three in 12.1 innings.
Justin Lawrence, RHP, Salt River (Rockies) — Lawrence is another bullpen arm generating a lot of interest from scouts, mostly because he delivers his 95-97 mph fastball, touching 100 mph, from a sidearm slot. That kind of heat coming from the third base side of the mound is especially tough for righthanded hitters. But the AFL’s TV audiences didn’t get to see Lawrence at his best, as he blew the save in both the Fall Stars and League Championship games.
Cole Tucker, SS, Surprise (Pirates) — Tucker may rival fellow shortstop Jazz Chisholm for being the happiest-looking player on the field, but the Phoenix-area product also impressed scouts with plus defense and an improved approach at the plate, resulting in a .370/.442/.457 slash line.
Abraham Toro, 3B, Scottsdale (Astros) — Toro wasn’t that well-known as a prospect coming into the AFL season, but he drew plenty of interest for more than just his backstory as someone who was born and raised in Quebec to parents from Venezuela. The switch-hitting Toro hit consistently all fall, posting a slash line of .348/.463/.561 with a good swing that barreled balls nearly every time at the plate. It’s a bat-dependent profile but with room for the hit tool to continue to develop.
Evan White, 1B, Peoria (Mariners) — White was already known for his plus-plus defense at first base, but he still surprised at least one long-time baseball evaluator who stated that the Mariners 2017 first-round pick was the best defensive first baseman he’s ever seen. White also showed his burgeoning power with six doubles and two home runs during his fall season after he lowered his hands during the regular season to keep his bat in the zone longer and get more elevation.