Since MLB Pipeline added tools grades to our prospect reports five years ago, we've tended to be conservative. Using the 20-80 scouting scale, we've rarely handed out a maximum 80 and have reserved that honor for the likes of Joey Gallo's power, Billy Hamilton's speed, Francisco Lindor's defense and Jose Fernandez's fastball.
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We'd never given any player an 80 for hitting ability, with the late Oscar Taveras' 75s on our preseason and midseason lists in 2014 representing our highest grades in that category. Until now. Blue Jays third baseman Vladimir Guerrero Jr. is that special.
Guerrero commanded a $3.9 million bonus as the top international amateur available in 2015, and he has proven to be better than expected. In 2017, his first year in full-season ball, he batted .323/.425/.485 between two Class A stops, finishing second in the Minors in on-base percentage and walking (76) more than he struck out (62) -- at age 18.
Guerrero has all the ingredients to be a superstar at the plate: bat speed, strength, hand-eye coordination, advanced pitch-recognition skills and command of the strike zone. He draws comparisons to Jose Cabrera or a more selective version of his father, who was elected to the Hall of Fame on Wednesday.
While Blue Jays shortstop/second baseman Bo Bichette Jr., Reds third baseman Nick Senzel, Yankees infielder Gleyber Torres and Padres second baseman/shortstop Luis Urias all are outstanding hitters, Guerrero clearly stood out as the best on MLB Pipeline's just-released Top 100 Prospects list. Here are other tools superlatives from the Top 100:
Best power: Eloy Jimenez, OF, White Sox
Jimenez generates tremendous raw power with his bat speed and leverage from the right side of the plate, and he has the hitting prowess to translate it into game production. He has increased his slugging percentage in each of his four pro seasons and slammed 19 homers in just 89 games last year as a 20-year-old. Scouts have likened him to Giancarlo Stanton.
Also in the running: Ronald Acuna, OF, Braves; Vladimir Guerrero Jr., 3B, Blue Jays; Shohei Ohtani, RHP/OF, Angels.

Fastest runner: Jorge Mateo, SS/OF, Athletics
Mateo's top-of-the-scale speed shows up on the bases, as he led the Minors with 82 steals in 2015 and 18 triples last season, when he finished third with 52 swipes. The winner of this category for the past three years, he's more than just a speedster, as evidenced by his 60 extra-base hits in 2017.
Also in the running: Ronald Acuna, OF, Braves; Anthony Alford, OF, Blue Jays; Estevan Florial, OF, Yankees; Royce Lewis, SS, Twins; Victor Robles, OF, Nationals; Taylor Trammell, OF, Reds.

Strongest arm: Shohei Ohtani, RHP/OF, Angels
Known as the Babe Ruth of Japan, Ohtani has a ridiculous six well-above-average tools: power, speed and arm strength as a hitter; fastball, slider and splitter as a pitcher. He threw the fastest recorded pitch (102.5 mph) in Japanese history and his arm plays as an 80 in the outfield, though the Angels plan on DHing him to conserve him for pitching during his first big league season.
Also in the running: Miguel Andujar, 3B, Yankees; Monte Harrison, OF, Marlins; Francisco Mejia, C, Indians; Victor Robles, OF, Nationals; Alex Verdugo, OF, Dodgers.

Best defender: Victor Robles, OF, Nationals
The lone player to make MLB Pipeline's All-Defense Team in each of the past two years, Robles does it all in center field. He gets the most out his 75 speed by working hard to refine his reads and routes, and his well-above-average arm strength dwarfs that of most players up the middle.
Also in the running: J.P. Crawford, SS, Phillies; Carson Kelly, C, Cardinals; Leody Taveras, OF, Rangers.

Best fastball: Hunter Greene, RHP, Reds
Greene, Ohtani and White Sox right-hander Michael Kopech all have reached at least 102 mph with their triple-plus fastballs, but Greene gets the nod because he generates his high-octane fastballs with the least effort. The No. 2 overall choice in the 2017 Draft, he has the quickest arm and the most athletic delivery some scouts ever have seen.
Also in the running: Michael Kopech, RHP, White Sox; Shohei Ohtani, RHP/OF, Angels; Riley Pint, RHP, Rockies; Alex Reyes, RHP, Cardinals.

Best curveball: Walker Buehler, RHP, Dodgers
Buehler's stuff, which already was good enough to make him a first-round pick in 2015, has taken a significant leap forward since he returned from Tommy John surgery that summer. He rushed from the Class A Advanced level to Los Angeles in 2017, his first fully healthy season as a pro, and Fangraphs rated Buehler's curveball's combination of velocity and movement the best in baseball during the second half of last season. It's an 82-85-mph bender with tremendous depth that plays well off his 95-100-mph fastball.
Also in the running: Dylan Cease, RHP, White Sox; Jay Groome, LHP, Red Sox; Forrest Whitley, RHP, Astros.

Best slider: A.J. Puk, LHP, Athletics
This was the toughest call on the list, as it was hard to separate Puk from the four other contenders listed below. He has a mid-80s slider with vicious movement, which allowed him to top the Minors in strikeout rate (13.2 per nine innings) during his first full pro season in 2017.
Also in the running: J.B. Bukauskas, RHP, Astros; Alex Faedo, RHP, Tigers; Michael Kopech, RHP, White Sox; Shohei Ohtani, RHP/OF, Angels.

Best changeup: Cal Quantrill, RHP, Padres
The son of former All-Star Paul Quantrill, Cal flashed a plus changeup as a Canadian high schooler and has continued to refine it. His change now qualifies as a well-above-average offering because he delivers it with the same arm speed as his fastball but it arrives in the low 80s and dives at the plate. The changeup is the main reason why Quantrill has been more successful against lefties than righties as a pro.
Also in the running: Kolby Allard, LHP, Braves; Anderson Espinoza, RHP, Padres; Stephen Gonsalves, LHP, Twins; Brent Honeywell, RHP, Rays; Jesus Luzardo, LHP, Athletics.

Best control: Mike Soroka, RHP, Braves
The Braves skipped Soroka a level to Double-A last year at age 19 because they figured he had the advanced pitchability to handle the challenge. He thrived, ranking second in the Southern League in ERA (2.75) and K/BB ratio (3.7) and third in walk rate (2.0 per nine innings) despite being its second-youngest hurler. Soroka commands four pitches, pounding the bottom and both sides of the strike zone.
Also in the running: Dane Dunning, RHP, White Sox; Jack Flaherty, RHP, Cardinals; Brent Honeywell, RHP, Rays; Jesus Luzardo, LHP, Athletics; Tyler Mahle, RHP, Reds; Sixto Sanchez, RHP, Phillies.