Scouts spend countless hours watching and evaluating players, carefully considering the appropriate grade for each tool or each pitch a player offers. Throughout the course of the season and particularly throughout the course of ranking season, grades are tossed around with near reckless abandon. This player has plus power, and that player has a below-average fastball. This player offers above-average hit projection while that player buries hitters with a potential plus-plus curveball. It's easy to talk about the quality of an individual tool, but what does it all mean in the context of other players?
In the second edition of the annual Top Tools Series, the Baseball Prospectus Prospect Staff debated long and hard over how individual players’ tools stack up against those of their counterparts. Drawing upon our own eyewitness accounts and opinions from scouts across the league, the team debated and compiled the following ratings. The end result is a product that captures the oft-missing context of how individual player tools compare and who has the best of each tool in baseball.
Previous entries: Best Hit/Power | Best Speed/Makeup | Best Infield Defense/Infield Arm | Best Outfield Defense/Outfield Arm | Best Catcher Defense/Catcher Arm | Best Fastball/Curveball
Slider
Top Slider in the Minor Leagues: Jonathan Gray (Colorado Rockies)
Despite having just 37 1/3 innings of professional experience, Gray made an impression on talent evaluators with a plus-plus slider that elicits ugly swings. Gray’s slider features extremely tight spin, approaching the plate with the appearance of a fastball before sharply darting away from right-handed hitters. At its best, the pitch has two-plane movement that misses bats consistently and can be relied upon in any situation. Gray shows a willingness to throw the pitch at any point in his sequence, making it all the more devastating.
Others Considered: Kohl Stewart (Minnesota Twins), Marcus Stroman (Toronto Blue Jays)
Plenty of sliders drew mention in this discussion, but Stewart and Stroman stood above the rest. Stroman’s slider shows as a plus-plus offering thrown in the mid-80s with lethal bite. Stewart has some projection remaining in his slider, but he routinely fires better-than-plus present sliders, featuring his own mid-80s velocity and slightly less sharp break than Stroman. Stewart could still refine the pitch further and has a chance to top this list in the future.
Top Major League Slider: Yu Darvish (Texas Rangers)
All-Time Tool: Steve Carlton
How to Identify It: The slider is best defined as a harder breaking pitch with both horizontal and vertical movement. Usually 5-9 mph off the fastball, the slider is thrown much like a fastball with grip, finger pressure, and hand angle creating the movement of the pitch. The grip is similar to the curve in that the index and middle fingers are closer together, generally on one seam of the ball. The thumb position remains the same as it does with a fastball, centered or just off under the ball. While the movement of the fastball is largely determined by pressure of the index finger, the movement of the slider is largely determined by having the middle finger up against the seam.
Pitchers will throw the slider from various spots on the horseshoe of the ball, depending on comfort. The hand should be slightly supinated at release point, with the wrist then snapping down like it would when throwing a fastball without having to twist the wrist to create movement. The best sliders will have a two-plane movement (10-4 for righties, 2- or 3-to-8 for southpaws) with a late darting action that is difficult to pick up. The lower the arm slot, the more “sweepy” the pitch will become, staying on one plane and losing the vertical effect. Many situational pitchers will have a sweepy slider, but they also have a much wider horizontal break that will start behind the same-sided batter and be very difficult to see. —Steffan Segui
Changeup
Top Changeup in the Minor Leagues: Marco Gonzales (St. Louis Cardinals)
Few pitchers can ride one secondary pitch all the way to the major leagues, but Gonzales should be able to do just that. Multiple scouts surveyed for this piece were aggressive in rating Gonzales’ changeup, pushing an 8 into the conversation and citing tremendous arm speed/angle deception and good movement. He throws the changeup in any count with confidence, showing a unique willingness to throw the pitch back-to-back when hitters appear particularly out of sorts. Gonzales’ changeup makes his entire arsenal better, helping his fastball play up and allowing him to keep hitters off balance when they think they may be getting another heater or a breaking ball.
Others Considered: Miguel Almonte (Kansas City Royals), Edwar Cabrera (Colorado Rockies), Ismael Guillon (Cincinnati Reds), Braden Shipley (Arizona Diamondbacks), Lewis Thorpe (Minnesota Twins)
Numerous pitchers enter the discussion when looking for potential plus-plus changeups, including young international signings like Miguel Almonte and Lewis Thorpe, both of whom have a chance to dominate hitters with the pitch. Braden Shipley’s changeup was a grade behind Marco Gonzales’ in last year’s draft, but he can still induce feeble swings on a consistent basis with a change that could get to the plus-plus level. Though Ismael Guillon cannot control anything in his arsenal, his changeup is still a thing of beauty, earning occasional plus-plus grades and giving scouts something to dream on.
Top Major League Changeup: Cole Hamels (Philadelphia Phillies)
All-Time Tool: Pedro Martinez
How to Identify It: A truly well-executed changeup can make the best of hitters look feeble due to the deception it creates relative to the fastball. The key to both executing and identifying a good change is the pitcher’s arm slot and arm speed, which should be nearly indistinguishable from their appearance when he throws the fastball. When the pitcher's arm speed or release point wavers, the offering suffers, because it look different to an opposing hitter’s eye. Young arms typically show some inconsistencies with these important aspects of changeup delivery in the early stages of their development.
After zoning in on the release and consistency of the pitcher's changeup arm action, a scout should assess the pitch's movement (or "action"). Some arms can get the first piece of the puzzle down but struggle with the grip and feel, often leaving the offering prone to “floating” in the strike zone. A good change is buried in the back of a pitcher’s hand, with a loose wrist to turn it over and trust to feel the grip with the pressure points of the fingers. Consistent action, or what appears like a deepness to the pitch—whether it is in the form of tumbling, “bottoming out” at the last instance, or fade toward the arm side—is a leading indicator of whether the pitch has the potential to miss barrels. —Chris Mellen
Command
Top Command in the Minor Leagues: Kyle Hendricks (Chicago Cubs)
It's difficult to find minor-league pitchers with true command, a skill that comes with experience and polish, but Hendricks has it in spades. Hendricks displays exceptional command of his entire arsenal, particularly his fastball, which he moves around the zone with ease. His knack for hitting spots and even moving the ball outside of the strike zone at will has enabled him to become a more highly regarded prospect than his raw stuff would suggest, and it might be enough to carry him to the big leagues.
Others Considered: Ty Blach (San Francisco Giants), Dylan Bundy (Baltimore Orioles), Rafael Montero (New York Mets), Justin Nicolino (Miami Marlins), Marcus Stroman (Toronto Blue Jays), Noah Syndergaard (New York Mets)
Blach offers a plus command profile that helps his arsenal play up a half grade and gives him a chance to sit at the back of a major-league rotation. Bundy and Montero can both locate each piece in their repertoire when they are at their best, and both should be quality big-league arms. Stroman and Syndergaard have different command profiles than the rest of this group, but for true power arms, both move the fastball around the strike zone and can paint when they're going well.
Top Major League Command: Hiroki Kuroda (New York Yankees)
All-Time Tool: Greg Maddux
How to Identify It: Command is the backbone of a pitcher’s game and often the difference maker in how well his stuff will play up. An arm can throw hard or snap off a nasty breaking ball, but if the pitcher can’t put his stuff where he wants it, its effectiveness is neutralized. Command should not be confused with control, or the ability to throw strikes. Command is the ability to consistently throw quality strikes in all four quadrants of the zone, while also demonstrating frequent accuracy in hitting the catcher’s target. At times, this can manifest by putting a fastball just off the plate for a batter to chase or snapping a breaking ball just below the knees.
The foundation of identifying command lies in the frequency with which a pitcher hits the target placed for him, along with how much of the plate his strikes typically grab and the variability he shows when working in or around the different layers of the strike zone. A fastball clocked at 95 mph would be clocked at 95 mph at any level. However, a 95 mph fastball in a hitter’s count at the belt in the middle of the plate in the lower levels may end up swung through or fouled back often, while the same fastball is likely to end up a souvenir 400 feet away in The Show. It’s important to evaluate a young arm's offerings independent of positive or negative results. The process boils down to these questions: Did he throw it where he wanted? Where was it on the plate? And can he throw the pitch to multiple spots with consistency? —Chris Mellen
Article discussed and debated by the Baseball Prospectus Prospect Staff. Constructed and delivered by Mark Anderson.
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How close was Randy Johnson to being considered the best all-time slider? Curious because I don't think anyone stands up to that over the course of my lifetime.