With this thread, I'd like to make the baseball education we got more explicit. Let's compile a guide - right here - on how to appreciate baseball and follow the nuances of this game we all love.
The inspiration for this thread was a great post by Kenny F'ing Powers over in the football forum, where he broke down exactly how to watch linebackers to appreciate what they're doing and sift the good from bad. In this thread, people should post guides to anything they find interesting about a baseball game between the lines. Things like:
- How you watch a batter's stance or swing
- Pitching mechanics
- How a prospect develops and what to watch for
- Managerial tactics, including bullpen use, play calls, etc
- How a pitcher sets up a hitter (or vice versa)
- Defensive positioning
- Pitch type identification
- How to spot the telltale signs of a tiring starter
The ground rules for the thread are mostly common-sense:
- This doesn't have to be PhD-thesis-level stuff. Imagine you're talking to a beginner, who knows the basic rules and has watched a few games, but not much else.
- Submissions of any length are fine as long as they're in the spirit of the thread. You don't need to be Charles Dickens here, some of us are just long-winded. A post explaining the infield fly rule is just fine.
- Paeans to specific players or teams of old aren't so useful, except as examples in service of a larger point. This isn't a history lesson.
- You don't need reams of evidence to submit as proof of anything. Explain something subtle which you've spent some time thinking about, and you'll naturally come off as an expert.
- When responding to someone's guide on a particular subject, free to clarify, amplify, further explain, or even rebut with an alternate view. But don't extend it to a discussion - state your point of view, and let people start a separate thread if they really want to have a back-and-forth. Dopes are invited to break out side conversations as they form.
With all that said, here's my kickoff:
I'd like to talk a bit to the psychology of the pitcher-hitter dynamic and share what I've learned about pitch selection.
So first of all, broadly speaking, there are 4 types of pitches in baseball:
1. Fastballs, usually 90-97mph, with minimal lateral movement. Meant to be the fastest pitch a pitcher throws, and can throw most reliably for a strike. There are variants on the fastball (two-seamer, sinker, cutter) which all break slightly differently, but we'll ignore those for now.
2. Curveballs, usually 70-80mph, thrown with heavy topspin to create a hard, downward break. Typically the slowest pitch a pitcher throws, can be hard to throw for a strike on-demand. Pitchers will often have days when their curveball command is good, and days when it's not (and they'll just not throw it, or not very much).
3. Sliders, usually 78-88mph, thrown 4-10mph slower than the fastball. Sliders break downward (there's a little of the curveball in its grip), but particularly break right-to-left (when thrown by a righty), across the plate and across the pitcher's body. Often looks similar to a fastball when it leaves the pitcher's hand, so if a pitcher can locate it, its deceptiveness can generate swings-and-misses.
4. Changeups, usually 72-85mph, thrown with the same arm action as a fastball but with a grip that causes the ball to go more slowly. The changeup, when thrown on a trajectory where a fastball would result in a strike, will end up diving down at the end (slower = more time for gravity), but also typically away from a pitcher's body arm-side (most typical with a circle change).
There are several other types (knuckleballs, splitters) but they are more rare and not important to the following points.
A lot of pitch selection comes from seeing how certain hitters respond to pitches they've seen, either in earlier at-bats or earlier in the count. First, some general guidelines:
- Most pitchers will throw a majority of fastballs, but certainly in the range of 50-65% depending on how many other pitches a pitcher has to mix in (major-league average is 59%). Often, a pitcher will attempt to "establish" his fastball early in the game, in the first inning or two, to show the other team that he has command of it and it needs to be protected against. A few pitchers (like Justin Masterson) throw fastballs much more often than this, but are typically throwing two-seam fastballs (or sinkers) which are designed to get ground-ball outs. Most pitchers, however are looking for swings-and-misses, so they'll mix up the pitch selection.
- In service of the previous point: batters swing and miss at fastballs less than half as often as they swing through an offspeed pitch. They also slug a lot better off fastballs. Curveballs, meanwhile, are put in play 20% less often and are hit for power less often.
- If a hitter is fouling off fastballs to the "opposite field" (i.e. not the side of the field they're standing on in the batter's box: foul to RF when batting righty; foul to LF when batting lefty), then it means they're a little slow in getting around on the fastball. In other words, they're really close to just missing it entirely, and are unlikely to put it into play with authority. You'll often see pitchers throw repeated fastballs in such situations, even though it deprives them of the element of surprise. I recall one at-bat in particular where Pedro Martinez was facing David Eckstein, who was unable to get around on his 93mph fastballs to the outside corner. After 5 or 6 of them, Eckstein finally swung and missed.
- If a pitcher is "forced" to throw a strike (a 3-0 or 3-1 count; sometimes in 2-0 or 3-2 counts depending on the base/out situation or the score), they will often go to their fastball. But a pitcher with terrific command of a curve or changeup will sometimes throw those, just for the extra element of surprise. A pitcher with high confidence, who has gotten a lot of swings lately, may even throw a ball if they're confident of getting a swing (particularly against guys like Jeff Francoeur who seemingly swing at everything). In one instance I can recall, Jonathan Papelbon threw a splitter on a 3-2 count with the bases loaded (i.e. where taking it for a ball would walk in a run), because he knew he could make it look like a fastball and would draw a swing.
- Conversely, when ahead in the count (0-2 and 1-2 especially), pitchers will throw fewer than half fastballs and dramatically increase the use of curves and sliders.
- If a batter has gotten a good swing on a fastball, and either fouled it straight back or hit it a long way just foul, it suggests they're seeing the fastball really well out of the pitcher's hand. Usually you'll see something "off-speed" (i.e. slower than the fastball - could be a curve, change or slider) as a result, just to change the hitter's timing and make them more uncomfortable.
- When facing a batter on the same side (Lefty pitcher / Lefty hitter, R/R), pitchers will usually have an advantage. They express this advantage by throwing many more sliders (~50%) and a few more curveballs, and fewer changeups.
More nuanced observations I'd offer:
- Pitchers are keenly attuned to a batter looking "off-balance" when swinging at a particular pitch. This may mean that their weight goes more forward than it should when reaching for an outside pitch, or they're less rooted swinging at an inside pitch, or their weight goes forward too soon or too late. If you watch a couple thousand at-bats, probably less than a full season of following a team, you'll spot when batters look uncomfortable. Pitchers will usually decide this has more to do with pitch location than with pitch type, and will often continue pounding a particular side (or seeming to do so, via slider/changeup) in the hopes that poorer balance = poorer contact ability.
- Many batters have "holes" in particular parts of their swing, where a well-located fastball can get a swinging strike an usually high % of the time. Pitchers will go to those holes, almost always with a fastball, when they have 2 strikes on the batter. For example, David Ortiz is well-known to have a hole on the inside half of the plate, from middle height and up. Pitchers may avoid these (for example, a hole on the low-and-away corner is pretty common), however, if the consequences (missing and walking in a run, say) are bad enough.
- After repeating more or less the same pitch for multiple pitches in a row, a pitcher will often go to a different pitch that appears to be the same pitch (and headed for the same location) as it comes out of the hand, but then veers or fades out of reach of the batter who was aiming at the same trajectory. If the repeated pitches were fastballs, a changeup or slider may produce that effect; if it was a slider (for an opposite-handed batter), going to the fastball will do the same. Seeing this pattern many times, you can come to predict when the pitcher is going to change it up. The hitter knows all this too, of course, and will be guessing alongside you.
- The longer into a game a pitcher goes, and particularly the more sliders and curveballs they throw, the harder it may become for them to generate the necessary torque to produce these pitches and reliably get them where intended. Towards the end of an outing, pitchers will often abandon the pitches in their arsenal that have a lot of left-right break, as that's hardest to control; they may keep throwing curveballs if theirs is mostly straight up-and-down; they'll usually keep fastballs and changeups. Hitters may adjust and start being able to more reliably predict fastballs, which can often lead to things getting crushed and a quick end to a starter's outing.
- In the course of their pre-game study of the opposing lineup, pitchers may plan out specific pitch sequences to use for certain opposing batters, based on watching film of those hitters and looking at their tendencies, vs certain pitch types and locations in certain situations. If they use one particular sequence (say, inside FB, outside FB, outside CB, inside CU, inside FB) and it has the hitter make weak contact or otherwise show vulnerability, they may use it again in the next at-bat vs that hitter. If a hitter seemingly expected one particular pitch in a particular count, and either nailed it or nearly did, they may change that one pitch to its deceptive equivalent. The point is: each pitch sequence sets up that batter's next pitch sequence, and looking at how pitchers adjust in that respect can be very interesting, particularly with successful pitchers.
- If a hitter was frequently calling timeout after pitches, they may be utterly confused, and the pitcher choosing to fuck with them (say, 3 straight changeups) may make them feel otherwise helpless. Confused batters will tend to do a couple of things more frequently: (1) Any pitch that starts at them and then breaks over the plate, they will swing at much less often; (2) They will swing at pitches that start over the plate and then break away from it more indiscriminately; (3) They may expand the strike zone on fastballs, swinging at things outside their normal disciplined zone.
Of course, these are general trends, not rock-solid laws of nature. But with increasing familiarity with specific pitchers, predicting their choice of pitch in advance can become a surprisingly reliable instinct. Further reading here.