AJ Minter is ridiculously good, if you didn't know. And has been for a while.
When he was coming up through Atlanta's farm, Minter had a decent amount of hype attached to him as a potential high leverage reliever. And when he made his MLB debut in 2017, he didn't disappoint with 26 strikeouts and 2 walks in 15 innings with a 3.00 ERA and a 0.96 FIP. By 2018, he was viewed by everyone as an impact arm out of the bullpen, ended up splitting closing duties with Arodys Vizcaino that season, and again, didn’t disappoint with his performance. Minter saved 15 games in 2018, with a 3.23 ERA and a 2.72 FIP. It looked like Atlanta had their closer of the future.
Then 2019 happened. It started ominously for Minter with a car wreck in Spring Training that hurt his pitching shoulder, and set him back three or four weeks. And once he did get back to pitching, he just wasn’t the same. Between injuries and bad performances, 2019 went about as poorly as anyone expected it to for Minter, who finished the season with just 29 innings pitched, and a 7.06 ERA.
That 2019 season, fair or not, brought serious doubt whether Minter was actually ‘the guy” long-term. Braves’ fans will remember 2019 as the year GM Alex Anthopoulos rebuilt the entire bullpen at the deadline, acquiring Mark Melancon, Chris Martin, and Shane Greene. All three were considered high-leverage relievers, and Minter was somewhat forgotten about. That winter, all three of those guys were retained, a minor-league free agent named Tyler Matzek was signed, and on top of that, the Braves added the top reliever on the free agent market when they signed Will Smith to a 3 year, $39M deal. When the 2019 season started, AJ Minter was the closer of the future. By the time the 2020 season started, he was sixth or seventh in the pecking order. It happens that fast with relievers.
Since the start of that 2020 season though, Minter has been nothing short of an elite major league reliever. And because Atlanta has consistantly had two or three or sometimes four guys above him on the depth chart, his ascension to this status has largely gone under the radar. When you’re great in the 9th inning, it brings all the attention and all the eyeballs, just as it does when you're terrible. But when your greatness is happening in the 6th or 7th inning, it’s a little harder to see, and not as many people notice. But make no mistake, going on the the last three seasons, AJ Minter has been a monster.
Since the beginning of 2020, Minter has pitched 86 innings, faced 350 batters, has a 2.84 ERA, a 2.49 FIP and has been worth 2.3 fWAR. That fWAR ranks him as the 12th best reliever in all of baseball since 2020, and only four spots away from teammate Kenley Jansen, considered one of the best closers of all time. In those 86 innings, Minter has struck out 98 batters and walked 31. I think most fans know Minter has been good the last couple of years. I’m not sure many of them are aware he’s been one-of-the-15-best-relievers-in-baseball good.
In those 350 batters faced, Minter has given exactly three home-runs. Three home runs in 350 batters faced. His 0.32 HR/9 innings is the second best rate in the majors behind only Dylan Floro. You might think, Minter must be a crazy ground-ball rate guy to give up so few home runs, but he really isn’t. His 43% ground ball rate over that period ranks 47th among qualified relievers. He doesn't give up homers because the dude is almost impossible to square up. Here’s his percentile profile for 2022:
So that's ridiculous. Here’s 2021:
And here’s 2020:
Look at the xwOBA for all three years: 90th percentile, 89th percentile, 99th percentile. Look at the xSLG: 90th percentile, 90th percentile, 96th percentile. Hitters struggle to ever square up the ball against AJ, when they make contact at all.
Another positive trend for Minter the last few years is how he’s improved his command. Here's his year-over-year walk rate:
Looking at this graph, it’s not hard to figure out where the problems in 2019 came from as well as where the improvement have come from since then. And in 2022, he's taken it to whole different level. With a career best strikeout rate of 39%, an ever decreasing walk rate, and the fact that hitters struggle to drive anything when they do make contact, Minter has already been worth 0.5 fWAR in 11 innings as a reliever, 6th best in baseball, and just behind Josh Hader. In those 11 innings, he has 17 strikeouts to 2 walks and his 0.94 FIP ranks 5th best in baseball. He’s been everything Braves’ fans dreamed he would be when he first came up.
We all thought Minter would eventually be a great reliever. And then 2019 happened and a bunch different relievers were added, including closers, and we all kind of forgot that was once supposed to be Minter’s job. Since then, he’s quietly turned himself into the elite arm we all dreamed on when he was destroying the minors. Is it easier to do in the 6th and 7th inning than it is in the 9th inning? Yes, of course it is. But don't mistake that for thinking it’s easy. Minter has worked his tale off from injury and ineffectiveness to become one of the best relievers in baseball. And people are starting to notice.