A.J. Minter and his 2022 breakout explored

The Atlanta Braves had an incredible regular season this year with many bright spots. The bullpen was one of them being tied for second in all of MLB in fWAR. A.J. Minter was a huge part of this contribution with 2.1 fWAR of the team’s 7.6. For reference, Minter was fifth in fWAR among all MLB relievers.

Of course, fWAR is an accumulative stat, and A.J. Minter pitched more innings in 2022 than he ever has in a season. However, his expected ERA (xERA) was also the best of his career at 2.39, showing that his high fWAR was much more than just being used in more innings than most relievers.

Minter’s xERA in 2022 was top four percent in MLB, even better than his 2020 output in which he had an ERA of 0.83.

What has changed for A.J. Minter?

The first thing that draws the eye is his walk, hits, and strikeout rates. His 1.9 walks per nine innings (5.5 percent rate) is the lowest for him since his debut year where he only pitched 15 innings. His strikeout rate of 12.1 strikeouts per nine innings (34.7 percent rate) is also his best since his debut season as well. Minter’s 6.3 hits per nine innings in 2022 is his second lowest since the COVID shortened 2020 season.

To put it in perspective, Minter’s K/BB ratio in in 2022 was 6.27. Other than those fifteen innings in 2017, Minter has never had a K/BB better than 3.14 way back in 2018.

So, what has caused on upswing in Minter’s K/BB rate?

Minter’s elite strikeout rate in 2022, which was top four percent in MLB, was obviously aided by the fact that he was not walking nearly as many batters, but is there another component as well?

Interestingly, some areas that you may think would be indicators of why Minter’s strikeout rate has gone up (besides less walks), does not point to any obvious reasons why. His whiff rate has been fairly consistent, and percentage of pitches inside the zone overall has been consistent.

The area that sticks out the most, as far as strikeouts goes, is that Minter is getting hitters to swing and miss inside the strike zone more. In fact, he has gotten better in this area every year since 2019.

Specifically, hitters swung and missed more against Minter’s cutter inside the zone this season by a large margin. In 2021 the whiff rate against Minter’s cutter was 19.7 percent. In 2022, the rate spiked up to 25.2 percent. This has led to all three of Minter’s pitches having a swing and miss rate of pitches inside the strike zone being between 24.4 and 25.9 percent. For reference, the league whiff rate inside the zone is only 10.7 percent.

Minter’s decrease in walks has been a big reason for his success, which has aided his strikeout to walk ratio, and his overall output. So, what is the story behind his ability to limit his walks in 2022?

In June of 2022, Ben Clemens wrote an article for Fangraphs tracking why A.J. Minter was having such a good season up to that point.

At that point there were a few areas that really stuck out. First, Minter was going after batters when they were in hitter’s counts more than ever. In June of 2022 when hitters had more balls than strikes, Minter threw a pitch in the strike zone 60.2 percent of the time. That would be the highest of his career other than his short 15 inning 2017.

Minter was also doing an excellent job of shying away from 3-ball counts up until June. As Clemens pointed out, the more pitches you throw during a count with 3 balls, the higher the probability of a walk. For example, a hitter can continue to foul off pitches with a 3-ball count, and all it takes is one bad pitch, and it results in a walk. Up until June 9th, Minter was at a 26.7 percent rate of 3-ball pitches per plate appearance, which is a career low since he was a full time MLBer.

Combine these two metrics, and it is a sure fire way to see positive results, especially when it comes to reducing walks. In June, Minter’s walk rate was at 4.4 percent. When the season ended, Minter still ended with a respectable 5.5 percent rate.

So, did this change in approach continue throughout the entire 2022 season?

For the entire 2022 season, Minter had 261 pitches in counts where there were more balls than strikes. Of those 261 pitches, 159 were in the strike zone. This equates to a 60.9 percent rate. Minter’s rate of going after hitters in hitter’s counts actually went up as the season went on by 0.7 percent from June 9th (which is when Clemens pointed out Minter’s approach), showing that Minter kept with what was working.

If we look at 3-ball pitches per plate appearance, Minter’s rate did go up a bit since June 9^th. For the entire 2022, Minter ended with a rate of 29.9 percent, which is 3.2 percent higher than it was on June 9^th. However, as can be seen from the original table, 29.9 percent is still the best rate of Minter’s career since becoming a full time MLB reliever.

Summary

At first, it may seem like a head scratcher when looking at Minter and the typical areas you would look at to see why he has improved, but in the end, he has just simply changed his approach.

Minter changed his approach to where he is going after hitters if they get into a hitter’s count and not shying away from throwing the ball in the strike zone in those situations. It appears he has gained confidence in knowing that hitters will swing and miss against his pitches inside the zone at a high rate.

By doing this, it has allowed for a lower probability of walks simply by staying away from 3-ball counts. Fewer pitches in a 3-ball count logically means there will be less walks, which has been the case for Minter.

Combine fewer walks, with the fact that all 3 of Minter’s pitches now have elite whiff rates in the strike zone, and it has resulted in Minter’s ability to be one of the best relievers in MLB when it comes to xwOBA (top 4 percent), fWAR (5^th in MLB for relievers) , and just about any other stat that matters.