Batters Can’t Stand A.J. Minter’s One Simple Trick

Even if you aren’t a Braves fan, you probably have a general idea of how their season is going so far. Max Fried? He’s still good, and still the ace for the defending world champions. Kyle Wright has taken a step forward and Charlie Morton has taken a step back. The hitters? You pretty much know them all; Dansby Swanson, Austin Riley, Ronald Acuña Jr., and Matt Olson lead the offense this year.

If you’re paying the barest bit of attention, you’d already know all of those names. They either starred in last year’s postseason, made headlines in a big offseason trade, or starred early in this season. When you get to the bullpen, though, you might be lost. Remember that stalwart relief crew from the playoffs? Will Smith has been abysmal, half a win below replacement level. Tyler Matzek has an ERA above 5, a FIP above 5, and an xFIP above 6. Luke Jackson hasn’t even pitched this year; he tore his UCL before the season and will miss the entire year.

Some of that slack has been picked up by new names. Kenley Jansen has been solid. Spencer Strider is electric, though he’s now a starter — nice problem to have. But the fourth member of last year’s bullpen quartet, A.J. Minter, is making up for the rest of his cohort’s absence. He’s off to the best start of his career, and one of the best starts of any reliever in baseball.

In some ways, Minter is like a lot of other relievers you’ve seen. His best pitch is a high-spin, high-velocity fastball. He backs it up with a breaking pitch that’s somewhere between cutter and slider, 90 mph with a touch of horizontal break. To keep righties honest, he also has a hard changeup. There are a lot of relievers who fit that general mold, and until this year, you might have easily lost Minter in the crowd.

Why bring him up, then? Surely, he’s just on a good streak, a few weeks and home runs away from just being another plus reliever instead of an unsolvable hitting riddle with an ERA around 1. Maybe that’s true. Maybe this is as good as Minter will ever be — and to be clear, it’s as good as most pitchers will ever be. But I’m interested in something else:

Yes, Minter is throwing fewer pitches in the strike zone than ever. He’s also walking batters at a career-low rate (excluding a 15-inning cameo in 2017 that I’m leaving off my charts). That makes about as much sense as clicking on a pop-up ad, but let’s see if we can disentangle what’s going on here.

First things first: “zone rate” is a blunt statistic. If you bounce a changeup on 0–2 trying to set up the next pitch or induce a swing, congratulations, that’s a pitch out of the zone. If you throw a fastball to the backstop on 3–0, that counts just the same. Raw zone rate isn’t going to account for those differences. That doesn’t make it a bad statistic, but it does mean that there’s some noise in it. So let’s dial the noise down by splitting Minter’s zone rates out into three groups:

Seems like we might be onto something. Minter isn’t doing any better at starting batters off with strikes, but when he gets behind in the count, he’s coming after them more often than before.

Except, nope! I tricked you here. It’s easy to look at percentages, say “oh those went up,” and move on with life. But Minter has thrown 93 pitches while behind in the count this year. The difference in zone rate there is basically two pitches thrown in the zone instead of outside it. If he were walking batters at his previous career rate, he would have walked 5.5 more batters already this year. Two extra pitches in the strike zone can’t be worth five walks. We’re back to where we started.

Here’s another idea: what if Minter is throwing fewer completely uncompetitive pitches, the type that opponents almost always take? Let’s create a new statistic, “zone-ish rate,” that encompasses pitches in the regulation strike zone as well as pitches just off the edges of the plate:

Curses! Foiled again. Are we just chasing ghosts out here? Minter is doing what he’s always done, throwing pitches near the zone at a league-average rate (zone-ish rate hovers around 70% across the majors), and suddenly he has a premium walk rate to go with his already ridiculous strikeout stuff. As an added bonus, he’s even striking batters out more than ever, too.

Here are some other busted leads. Batters are swinging roughly one percentage point more frequently and making contact at roughly the same rate. Minter’s first-strike percentage is down from last year, though it’s up from his previous career average. In other words, nothing significant has changed, aside from the fact that Minter went from walking everyone to walking no one.

Did A.J. Minter break my stat-loving brain? Is this it for plate discipline metrics? Heck, has anyone actually watched Minter play all of these games? Maybe the statisticians watching him just scribbled down any old thing after the game and said “eh, no one will be able to tell the difference.” Have I uncovered a great conspiracy at the heart of baseball?

Sadly — or happily, for my sanity — that’s not the case. Minter isn’t bending reality or altering the league’s books and records. I was just looking at him too abstractly. How do you walk someone? You throw them a pitch outside the strike zone in a three-ball count, and they take the pitch, which the umpire then calls a ball. You don’t walk someone by running a low chase rate, or by targeting the zone in a particular way, or anything like that. Three balls, pitch outside the zone, taken. It’s that simple.

How can you prevent this from happening? Let’s take them one by one. Three-ball counts? He’s reaching them less often than ever. If you want to think of it in a convoluted way — and I do — Minter is throwing fewer pitches in three-ball counts per plate appearance than he ever has before. You might think that the percentage of plate appearances that reach three balls is the right metric, but I disagree. If you reach a 3–2 count, then need ten pitches to put away the batter, that’s a lot of chances to miss. The more three-ball pitches, the higher the chance of a walk, and Minter has handled that this year:

That’s not enough to turn his walk rate down to zero, but it’s five-ish fewer pitches with any chance of walking anyone. That’s a step in the right direction; every three-ball pitch is a chance to lose your grip and sail one.

Next, a pitch outside the zone. Here, Minter’s results are mixed:

It’s not exactly the best he’s been, but it’s close to it. He’s mostly hitting the zone; other than 2020, when he averaged a three-ball count every two plate appearances, he’s right around his career mark. He’s around the zone almost all the time (and for reference, the league as a whole checks in at 77% there so far this year).

Why does being around the zone matter? Because the batter has to take to turn a pitch into a walk, and in a 3–2 count, you won’t find many batters willing to take a fastball on the edges of the plate when a called strike will end their turn at bat.

In 3–0 and 3–1 counts, Minter has thrown exactly seven pitches this year and walked the hitter on three of them. Batters have only swung at three of the seven; the last pitch was taken for a strike. That 43% swing rate is right in line with league average. Batters are no dummies; they’re happy to be patient when the best case is a free base and the worst case is getting to see another pitch.

That all changes with two strikes. Minter has thrown 17 pitches in 3–2 counts this year and drawn 16 swings. That’s because he attacks the strike zone; 15 of those 16 swings came on pitches that were either on or just off the plate, with the lone holdout a wild hack by Jesús Sánchez.

That difference in batter behavior — passive on 3–0 and 3–1, aggressive on 3–2 — is a league-wide pattern, though Minter’s 94% swing rate on 3–2 is high even for a swing-happy count (league average is 71%). It’s much harder to walk someone on a 3–2 pitch than on a 3–0 or 3–1 pitch for that reason. That sounds quite obvious — 3–0 counts always end in walks — but I’m talking about the individual pitch: 29.7% of 3–0 and 3–1 pitches have resulted in walks; only 23% of 3–2 pitches have.

That’s almost entirely due to a higher swing rate on fringe pitches. On 3–2 counts, batters swing at 66% of pitches that are off but near the plate. That rate is only 39% on 3–1 and 5% on 3–0. If you’re good at getting the ball around the plate, even if it’s not necessarily in the zone, then getting to 3–2 is a great way to prevent walks. Batters can’t walk if they’re swinging.

How does Minter reach so few 3–0 and 3–1 counts as compared to 3–2 counts? When it’s 2–0 or 2–1, he doesn’t take any chances with throwing another ball:

That’s good for a 92% zone-ish rate. In other words, 92% of his pitches are either over the plate or quite close to being over the plate, in the zone where you can sometimes get called strikes and often get swings. That’s nearly 20 percentage points higher than the overall league average, and a huge jump from his 70% rate last year. Minter is hacking the system, in other words, taking action before those dreaded 3–0 and 3–1 counts where a slight hiccup in command results in a walk.

I’m fairly certain that Minter’s 0% HR/FB rate won’t hold up all year. I bet he’ll strike fewer people out and walk slightly more than his current 4.4% rate. I’m not trying to tell you he’s the new best reliever in baseball. But he’s an interesting case study in what a pitcher can do to rein in walks without turning into Kyle Hendricks overnight.

Minter’s pitches aren’t moving much differently than they did last year. He’s not throwing more pitches in the strike zone overall. He’s not missing more bats. His CSW% is unchanged. All he did was make one adjustment — before he ever got to a 3–0 or 3–1 count, he’d dial in and throw something competitive — and presto, walks were gone overnight. That’s a great lesson in the importance of pitcher approach, and also in the limitations of figuring out what a pitcher has changed by looking at summary statistics.