Last week, the legendary Ben Clemens wrote about the bunt situation, because the bunt situation, as it turns out, is powerful. Hitters strike out more often, pick their spots better, and have more success. It is a renewal. He didn’t appear in Ben’s article, but Milwaukee’s David Hamilton leads the way, leading the league with 10 bunt hits and 23 bunts. It’s just the 12th time this decade that a player has hit 23 bunts in a season, and it’s already the middle of June! Ben noted that 74.1% of bunts were successful – meaning the bunt resulted in a hit, a defensive error, or a sacrifice bunt – which is the highest mark of any DH in the universe. With so many bunts in the air (and on the ground), I got to wondering how the pitchers could fight.
The first way to protect yourself is to change your posture. You bring in your third baseman, play the corners, put in a wheel play. But I wanted to appear in a different way. If you’re a hitter, and you want to make sure the batter at the plate doesn’t get a successful bunt, what can you do? The two biggest things you can control are your voice type and location. I got into Statcast data for bands and tried bands 18 years ago. This is not a shocking study, and some of my findings are accurate, but I’m not sure I’ve ever seen it laid out, and I’ve never seen the numbers behind it.
As Ben noted, most bunts are successful. Since 2008, 69.8% of the bunts in the game have been successful, which also means a hit, an error, or a sacrifice. Whether you approve or disapprove of the sacrifice, we count it as a success because that is what the bunter wanted. When nobody is on base and the batter gets a bunt down in the right field, it reaches base 46.3% of the time. IA .463 BABIP is very good, and holds true for all pitch types:
Bunt Success Rate None
| Type of Pitch | The Four-Seamer | The Sinker | The cutter | Curveball | Slide | Offspeed |
|---|---|---|---|---|---|---|
| Success Rate | 46% | 47% | 46% | 49% | 47% | 45% |
When you’re on the mound against the likes of David Hamilton, I’m not sure knowing that curveballs in a game have a 3.9 percent success rate over four-seamers and 4.4 points over offspeed pitches will affect your decision-making. That sounds like a very small difference. However, think of it as 40 points of batting average or on-base percentage. Maybe that should be enough to influence your voice choice. Curveballs aren’t as bad as this table makes them out to be, but we’ll get to that later.
That calls for a base hit with the bases empty, but what about getting runners on base? We’ll leave out situations with a runner on third, because that’s his can of worms, but here are the success rates by pitch type:
Belt Success Rate for First and/or Second Runners-up
| Type of Pitch | The Four-Seamer | The Sinker | The cutter | Curveball | Slide | Offspeed |
|---|---|---|---|---|---|---|
| Success Rate | 77% | 82% | 80% | 78% | 80% | 82% |
If you can get a bunt down in the right spot with runners on base, you have about an 80% chance of success. Once again, the spread between pitches doesn’t seem that big, but if you’re sure the batter is going to try to sacrifice himself, it might help to know that the success rate of four-seamers is 4.9 percentage points lower than that of offspeed pitches. Five percent of the points seems like an awful lot when success means at least one runner will get into scoring position.
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As for why four seamers are so difficult to get down, that part may be accurate. Four-seamers rise – or at least, fight gravity hard – giving them the best chance of making contact at the top of the bat, leading to aerial bunts. Here are the popouts and lineouts per pin in play:
Output level and Lineout
| Type of Pitch | The Four-Seamer | The Sinker | The cutter | Curveball | Slide | Offspeed |
|---|---|---|---|---|---|---|
| Popuut/Lineout Rate | 9.7% | 5.5% | 6.1% | 4.6% | 5.6% | 3.5% |
Four seamers ahead by a mile here. If you throw a four-seamer and the batter puts it into play, they have about a 10% chance of getting outs. That’s pretty high, and you can make it higher by pitching well. As you would expect, high scores appear more often. Here are the same numbers, but this time only for pitches in the upper third of the zone or just above the rim:
Output and Line Ratio (High Tones)
| Type of Pitch | The Four-Seamer | The Sinker | The cutter | Curveball | Slide | Offspeed |
|---|---|---|---|---|---|---|
| Popuut/Lineout Rate | 11.3% | 7.7% | 9% | 4.9% | 7% | 4.9% |
Overall, 57% of bunts turned into popouts or lineouts by four-seamers. If you have your third baseman playing shallow, or if you’re a sports hitter, throw a four-seamer. It’s your best chance to induce a popout bunt out of the backfield. All of this is accurate enough. After doing all my research, I asked a friend who is much smarter about baseball than I am what he thought the best pitch to throw to a bunter was. He didn’t hesitate: fastball up and in. So far all the numbers I’ve shown you prove that, but I’ve only shown you the numbers of balls in play.
I’ve told you before that curveballs aren’t as bad as they seem. They tend to leave the bat on a downward trajectory, which is great if you’re trying to get a bunt down. But before they leave the bat on that downward path, they must communicate with it. Turns out that’s a challenge, because as with regular swings, vertical breaks are key to the lack of bats in belts. The primary function of the curveball is to drop, and it tends to drop below bunter bats. This one is clever, but these are beautiful paintings, with respect Baseball Prospectus The brilliant Bradley Woodrum helps show why pitching is especially useful for lost bats (and before you accuse me of only knowing one adjective, please consider the possibility that both Ben and Bradley are really smart):
Bradley wasn’t writing about bunts when he made these sketches, but I think you could argue that they are a better fit for bunts than regular swings, since hitters tend to change the angle of the bat less when swinging than when swinging normally. The table below shows the rate of broken or missed bands for each tone type. The curves are higher, and they don’t close too much:
Foul and Whiff Rate
| Type of Pitch | The Four-Seamer | The Sinker | The cutter | Curveball | Slide | Offspeed |
|---|---|---|---|---|---|---|
| Miss/Evil | 48% | 53% | 52% | 64% | 59% | 56% |
If your goal is to make it as difficult as possible for the batter to get the bunt down in the right spot, throw a curveball. A curveball is 32% more likely to create a whiff or foul than a four-seamer. Specifically, throw a low curveball. The average successfully bound curveball crosses the plate at a height of 2.65 feet, while the average curveball that is bound or missed on a bunt attempt is just 2.01 feet.
First I showed you the success rate for the belts in play, then I showed you the hit and miss rates. Now, let’s put all the bunt attempts together. Here is the success rate for each pitch:
Overall Belt Success Rating
| The Four-Seamer | The Sinker | The cutter | Curveball | Slide | Offspeed |
|---|---|---|---|---|---|
| 35.4% | 33.9% | 33.1% | 24.1% | 28.5% | 30.3% |
Four seamers may have the best chance of inducing a popup, but because they miss so few at-bats, they don’t. very simple to convert to a successful bunt. If you throw a four-seamer to a batter who squares up on a bunt, too, he is 32% more likely to reach base or advance a runner than if you throw a curveball. I even ran the numbers and put four seamers on the top and inside, just to be sure. I looked at the positions highlighted in the diagram below, Attack Positions 1, 2, 11, 12, 21, and 22, and right-handed hitters only:
If we limit things to these seamers found on the top and inside, the success rate is actually high! It’s true that the success rate for bunts in play is slightly lower – with two percentage points lower for these four seamers than for all other four seamers – but these spots are very, very easy to incorporate into the play. The rate of dirty and missed belts decreased from 56% to 45%. It turns out that if you’re looking square for the ball and the ball is coming right in your face, you’re more motivated not to miss. That brings the overall success rate up to 62%. They might make the batsmen look very uncomfortable, but suddenly, these four seamers up and inside are equal. Easier to bunt, and that’s not counting all the hit-by-pitches caused by batters squaring up to bunt and not being able to avoid fastballs up and in. I have no way of determining how often that happens, but we’ve all seen it many times, and I suspect the number doesn’t mean anything.
We don’t have the numbers on the pitches where the batter reaches the bunt and takes the pitch, which is a big hole here. I think it is possible that four seamers are called strikes and fewer balls than other pitches, which would increase their value. Even then, however, it would take many called strikes to make a difference.
If you’re sure that the batter is going to bat no matter what, that he’s going to take a lot of cracks at it and bounce back with two strikes, then blasting them and going in with a four-seamer at the start of the count might be a smart play. They have a good chance of getting one of those three tries, so throwing the field with a low success rate for bunts in the game makes sense. But if you’re down to two strikes, or if it’s early in the count and you just want to make sure the bunt doesn’t go down at all, the breaking ball is a smart move.
All stats are in for the June 12 games.
