Last week I kicked off this series with a primer, to which I will refer you with questions on the nature of this beast. For our first foray into the weeds this week, I was piqued by a question in my chat queue last week about the difference between bat speed and power. The latter is a topic I’ll surely spend a bunch of time dissecting in this space over the weeks to come, because who plays in a dynasty league and isn’t willing to trip a sibling in order to read about power-hitting prospects? For today’s run, though, we’re going to talk about bat speed.

It’s a skill that can be on the more difficult side to identify for the untrained eye—most swings taken by professional baseball players are, after all, objectively quite fast. And it’s one of those terms that even mainstream prospect reports written by not scouts will utilize frequently without much context about why it’s important. Intuitively it makes sense: if you swing faster, you have a better chance of hitting a ball that has been pitched fast. But understanding how and why certain players have better bat speed than others is useful when trying to map out valuation and a long-term dynasty league strategy.

So let’s take a shallow dive into what bat speed is, why it’s important, and why some prospects are better targets in your league than others because of it.

The relationship between bat speed and strength

Of course there’s a relationship between bat speed and strength. There is a direct connection between pitch speed, bat speed, and the velocity of ensuing contact. And, more broadly, being physically strong usually is advantageous when attempting physically rigorous exercises.

There have been studies reaching conclusions about a very strong correlation between upper body strength and bat speed, and it matches the intuition test. The more physical strength you have, the greater the muscle mass within which you impart energy, and the quicker you can generate greater force. You need strength in the shoulders to build the initial rotational momentum. You need wrist and forearm strength to start the barrel and whip it through the hitting zone once underway. You also need those arms and wrists to keep that barrel in place, coasting along the most-efficient plane while you do it. You need strength through your biceps, and obliques, and pectorals to maximize power and extension through the point of contact.

But as one AL East scout explained, “The largest misconception about bat speed is that it stems from brute physical strength. Especially with a wooden bat, bat speed is much more a function of small quick-twitch muscles in the hands, wrists, and forearms.” This was the closest thing to a true consensus among the half-dozen folks I talked to, nearly all of whom carefully noted that bat speed is primarily the product of particular pockets of strength in the arms and hands.

Good bat speed does not equal good hitter, and not all bat speed is created equal

But before we get into the effects of quality bat speed, we caveat! It is important to remember when discussing bat speed that, as with any other component of a skill, it is not singularly determinative. Just because a player can whip the barrel though the zone at a good clip does not make him the next Ted Williams. Bat speed is not, as one evaluator put it, “some end-all, be-all." There are players with great bat speed who don’t hit so well; case in point, the best bat speed around right now is Javy Baez, who is a career .242 hitter.” Plenty of hitters with quality bat speed lack the kind of hand-eye coordination, pitch recognition, bat path consistency, or any combination of other things to take advantage of that bat speed and produce consistent, quality contact.

Beyond those issues, the manner in which a hitter generates his bat speed can have varying degrees of impact on things, too. Hitting instructor and prospect team member Derek Florko explained that when you’ve got a swing that relies solely on the torque of the hands and wrists through the zone—after the bat is already in motion—“the bat won’t accelerate until [the hitter] commits to swinging.” That kind of bat speed, where “the bat is accelerating in front of [the hitter], after he pushes the hands forward,” is late bat speed, and it is less helpful for making in-swing adjustments.

Early bat speed, though… now that’s the good stuff. Early bat speed, Florko continued, “is not generated by the batter pushing the hands forward, but by launching the barrel, pivoting the forearms, and creating that bat speed away from the ball that gets pulled forward by the hitter’s rotation.” Think about when you watch Miguel Cabrera hit, and how explosive that first hand movement is at trigger. That initial spark of force creation, that’s the key moment in the swing for producing the good kind of bat speed. A hitter shouldn’t be looking to get a train rolling out of the station when he triggers. He should be looking to create a supersonic boom like one of them funny cars with the parachutes on ‘em.

But a good hitter does need good bat speed

“Bat speed is important,” one AL West scout noted. “We’re not scouting anyone with 20 or 30 bat speed. I'm not sure how you hit fastballs with that. The slower the bat, the more efficient of a swing is needed to project hit tool.” As I alluded above, there is just a lot that has to go right in a given swing for quality contact to ensue, regardless of the raw speed at which the bat travels. The hitter must navigate two planes of trajectory between the swing and pitch plane, make proper adjustment to ball flight in order to sync and time the swing process, and angle for a specific locus on the bat’s barrel—the sweet spot—in order to generate the contact. Bat speed is but one variable within the much-broader matrix of hitting.

It is, however, a uniquely valuable component. It helps cover up for timing or barrel delivery issues along the way. It creates margin for error. And when you’re talking about one of the most difficult mental and physical acts in sport, one that affords less than half a second of reaction time, any little bit of advantage to that end is a critical one.

Steve Givarz on the prospect team agreed: “For me, bat speed is a very big deal. Having premium bat speed helps you catch up to velocity, late movement, and breaking balls. As pitchers are throwing harder than ever, the time you have to react keeps decreasing, and having a quick bat can give you more time to catch up to the baseball.” The more bat speed, the more flexibility a hitter has to cover different corners of the zone and adjust to different trajectories when fooled.

Beyond those extra pitches a player can hit thanks to his bat speed, there’s also an added benefit of helping him recognize what he can’t hit. An AL East scout broke down this element of the equation: “Players with quick hands can also hit for higher averages because of the pitches their bat speed allows them to not swing at. I know sounds a bit counterintuitive, but when a guy knows he has very quick hands, he is aware that he can throw his hands at the ball later than most batters. It allows the hitter to have confidence waiting back on a pitch—not having to commit to a certain spot early.” Again, it’s that extra split-second or three of reaction time that gets saved on account of the barrel taking less time to explode through the zone.

Those extra milliseconds are eternities in the world of hitting, and the ability to buy extra eternities is a significant advantage for a batter—one that makes it a lot easier to project success against the best pitchers in the world.

The kids with the goods

Of the half-dozen scouts and prospect team members I spoke to for this piece, the players below were discussed as some of their favorite examples of quality bat speed among current prospects—both professional and amateur. So let’s take a look at how the relatively awesome bat speed of these hitters translates to their dynasty league values present and, potentially, future.

Alex Verdugo (OF)—Los Angeles Dodgers (Triple-A Oklahoma City)

Verdugo utilizes a one-piece swing, where his progression through the load, trigger, and fire is all a single progression of continuous momentum-generation, with everything moving in one direction; there’s no hitch, and he creates plus bat speed with efficiency of motion. His wrists and forearms stay very quiet while building tension during the load, and he fires the bat head into motion from a near standstill. The process in Verdugo’s swing limits the amount of separation and leverage he can create with the ensuing swing plane, to where raw power that pushes plus will likely play down a full grade, to more like average in games. But it allows him to get the barrel to the point of contact with striking quickness, and the bat-to-ball ability has shown up thus far in the form of strikeout numbers that, especially when adjusted for his extreme youth relative to league-average age at each stop, push elite.

Verdugo isn’t a prospect likely to grow into 20-plus homers, and given his fringy speed that certainly limits his fantasy ceiling. But the hit tool has a chance to be quite good, thanks in no small part to his top-shelf bat speed. I wouldn’t go nuts trying to overpay for him, particularly in shallower leagues. But Ender Inciarte-type value ($14 mixed league value last year) is a wholly reasonable expectation, albeit with the power and speed tallies reversed, and that’s a sneaky good player regardless of format.

Clint Frazier (OF)—New York Yankees (Triple-A Scranton/Wilkes-Barre)

Frazier could just be the reigning title-belt holder for best minor-league bat speed, and he was cited by three of six. There is some effort to Frazier’s swing, and sometimes he’ll overdo it and come out of his launch mechanics in the process. Frazier’s a perfect example of the kind of hitter where elite bat speed can make up for a number of other deficiencies in the swing process, as his bat path often is not particularly direct, with a looping action into the zone that can cut off his inner-third coverage and add length to the swing in spite of the barrel velocity. Obviously as an elite hitting prospect—we had him 10th on our pre-season Dynasty 101—but he’s the kind of hitter I’d most willfully target in a rebuilding situation on account of the elite bat speed.

Nick Senzel (3B)—Cincinnati Reds (High-A Daytona)

I noted Senzel’s quick trigger on the Cape a couple summers ago, and he’s only gotten better and crisper with his barrel delivery since. His swing is a great example of the late bat speed Derek was talking about, as you can see the hand and forearm strength is really on display at the trigger in these swings. He’s able to generate outstanding early velocity with the bat head, and stay short to the ball while doing it.

Adam McInturff’s notes in his Eyewitness Report from this past June confirm the top-shelf bat speed: “Quiet trigger allows him to stay back on breaking stuff; commits late, able to spoil good pitches; limited holes in swing.” Those are all of the things we’ve been talking about, rolled up into one neat, little line-drive machine. Obviously as one of the top bats in last year’s draft class, Senzel is no stranger to anyone even in your shallow, handful-of-prospects-kept league. But the underlying hitting tools here suggest he’s a good bet to be worth every penny of the acquisition price down the line.

Jorge Ona (OF)—San Diego Padres (Low-A Fort Wayne)

Video courtesy of Eric Longenhagen/FanGraphs

There’s still a cloud of mystery hanging over Ona, who didn’t play until fall instructs after signing a $7 million deal with the Padres in July. Prospect teamer Nathan Graham identified Ona’s bat speed as the standout from his first weekend of games at Fort Wayne, which is an intriguing development. The swing looked a bit on the rigid side in the above video from instructs last fall, with a mechanical lower half that gave the appearance of vulnerability to speed changes.

But you certainly can see flashes of the wrist and hand strength in that swing, and the Padres clearly bought into the idea that his hit tool would develop enough to translate plus-raw power into game action. Especially given the visceral appeal of big-money Cubans in dynasty leagues (we can’t help ourselves, can we?) Ona’s a guy with some helium potential this spring if he does some damage in the Midwest League.

Monte Harrison (OF)—Milwaukee Brewers (Low-A Wisconsin)

Video courtesy of Eric Longenhagen/FanGraphs

Harrison is a classic case of a true athlete—he was a three-sport star in high school, and when I say athlete I mean athletehinting at the right kind of physicality to become a really dynamic baseball player, but showing such sporadic glimpses that it’s hard to totally buy in. The Brewers’ second-rounder in 2014, his career to date has been marred by injury, with a broken ankle shelving him for half of 2015 and a broken hamate bone knocking him out for most of the summer and sapping his power upon return last year. Harrison falls into the category of “late” bat speed guys at this stage of his development, and has struggled to develop the timing and hand-eye to develop consistency with his swing when he has been on the field.

The raw tools of superstardom are here, however, and he certainly has the premium strength, physicality, and bat-speed building blocks you look for to translate into a quality hit tool. It’s something of a make-or-break year for him in the Midwest League, but if you’re looking for a lottery ticket that is unowned, even in deeper dynasty formats, he’s a guy for the radar this spring.

Bo Bichette (SS)—Toronto Blue Jays (Low-A Lansing)

I touched on Bichette pre-season in my Ocean’s Floor piece on shortstops, and he has come out of the gate raking in the first week of Midwest League play. That swing right there is one of the most interesting you’ll see load-wise, and one of the more impressive you’ll see bat-speed-wise. He loads deep off a big leg kick that can make him unbalanced when he starts his weight transfer, but by and large he corrals his momentum well, and you really can see the hand and wrist strength on display at trigger. This is deep bat speed, and it is pretty elite bat speed. It remains to be seen if the balance and consistency is good enough to allow him to make in-swing adjustments against higher-minors breaking pitches, but so far, so good.

Toss in the big-league bloodlines and athleticism that is borderline good-enough to stick up the middle, and there’s a bit of a Javier Baez vibe to the bat. He’s a guy to get in on now as a ceiling play where he’s still available, lest he continues to put up the kind of video-game numbers he’s put up thus far as a professional, and force his way to High-A by mid-summer.

Jordon Adell (OF)—Ballard High School

Adell’s another kid I touched on in the Ocean’s Floor, and his bat speed is the standout kind in this draft class. As Jeff Long described it, “His swing is just quick to the ball, but with a lot of power. He has great rhythm at the plate, and has tremendous hand speed.” You can see that hand speed in this swing here, where the quick-hitch load sets up a lightning-fast trigger and barrel delivery. That swing produced a 95 mph exit velocity off a 75 mph pitch, which tells you about the kind of force he’s generating as a 17-year-old. He’s still growing into his body, and the swing mechanics are extremely inconsistent at present, to where concerns about how the hit tool eventually will actualize are likely to, at least, mildly dampen his draft stock. But if you’re going to bet on projection for a hit tool, you’re best to bet on projection for a kid with this kind of bat speed.