The combination of bicep tendinitis and a sprained ankle kept Orioles left-hander Bruce Zimmermann on the injured list for more than three months of his 2021 rookie season. But that time also allowed him to make an improvement that has him experiencing early season success.
Zimmermann, who will start the second game of Sunday’s doubleheader with the Kansas City Royals, has a 2.59 ERA through five starts, a mark that was even better before a scoring change tacked three extra earned runs onto his record. Still, he’s off to a strong start to his second major league season largely by building on the areas he succeeded as a rookie, particularly his secondary pitches.
Among pitchers who have thrown at least 100 breaking balls in 2022, Zimmermann is one of only two who has yet to allow a hit on one of them, according to Baseball Savant. Two-thirds of the at-bats he’s ended with a slider have resulted in a strikeout, with that pitch’s 57.6% whiff rate — the percent of swings that result in misses — ranking fourth among nearly 200 sliders that have induced at least 25 swings and the highest among all left-handers.
His slider and curveball have combined for 32% of his pitches, matching his 2021 usage. Yet, he’s deployed his four-seam fastball 10% less often, lowering his use of a pitch that was hit hard in 2021; Zimmermann’s .711 slugging percentage allowed on the pitch was the highest of any major league four-seamer thrown as much as his. The trend has continued in 2022, with opponents hitting .480 off the pitch, which has been about 1 mph slower on average than it was last season.
He’s funneled some of his usage of the four-seamer to a changeup that he worked to improve while rehabbing the bicep injury, while also adding a one-seam fastball — a pitch with a similar profile to a sinker — to his repertoire. The former has been a neutralizer; entering Saturday, only one left-hander has struck out more right-handed batters with a changeup than Zimmermann.
A 27-year-old Ellicott City native, Zimmermann is one of the few pieces from the Orioles’ 2018 trade barrage who have established themselves in the majors; he was part of the package acquired from the Atlanta Braves for pitchers Kevin Gausman and Darren O’Day. Earlier this week, Zimmermann talked with The Baltimore Sun about the adjustments to his changeup his, why he felt they were needed and why his secondary pitches his play so well off his struggling fastball.
Note: Questions and answers have been edited for brevity and clarity.
You’ve spoken a bit after starts about how you spent sometime before this season working on your changeup. Why was that pitch a focus for you, and what changes did you make?
Traditionally, I was always a two-seam fastball guy, all through college and halfway through the minors, and then I switched to a four-seam fastball. Analytical speaking, it was playing better than my two-seam, so when that happened, I still wanted to keep the two-seam grip on my changeup because I liked the depth that I got because it generated more ground balls, it had more sink than run, all the good stuff for double plays, and whatnot. Then, because I was throwing my four-seam [fastball] and then a two-seam changeup, it was kind of blending between the two, and I was losing that depth that I needed on my changeup to make it the kind of pitch that it was, ’cause it’s not a massive speed difference [from my fastball]so I need that action for it to be as successful as it is.
While I was in rehab last year for the bicep tendinitis, there was a time when I was just playing catch, and I remember I just was fiddling around with different wrist positions. Not changing the grip. Just changing the wrist positions, and something clicked with something I changed that gave me the depth back to my changeup. I took that into the offseason and really started like working away at finalizing the distinction between how I was manipulating the ball at release between the four-seam and the changeup to really get the difference between the ride and the sink. Then, the end of spring training, beginning of this season, kind of figured out something else with the placement of one of the fingers I had on one of the seams, and that seemed to give me even more security to really kind of throw with even more intent, because it’s kind of a high-spinning changeup. [Note: Entering Saturday, the average major league changeup has a spin rate of 1,738 rpm this season, while Zimmermann’s has a spin rate of 2,022 rpm, 12th among 96 pitchers who have thrown at least 50 changeups.] With figuring out the last little bit about the finger placement with the wrist positioning, that’s what’s been able to kind of make it to pitch that is now different from in previous years and why it has that late life to it.
What do you mean by wrist position?
Normally when you throw a four-seam fastball, you want to throw it with kind of a 90-degree angle [between your hand and forearm], so you can get behind it and you push it and you backspin it really well. When I was doing that with my changeup, it was flattening it out, and it was just kind of running arm side, and so it was staying in the barrel zone basically. Whether it would go off the end of the bat or — it was in barrel zone. Instead of feeling that, I tried to flat-wrist it and keep my wrist flat through it, and keeping that flat wrist allows me to get the two-seam action. It just allows me to get to the inside of the ball with more force and get it spinning at the right axis to get the actual depth, not just the run.
So that was all just a product of playing catch?
Literally just kind of stumbled upon it during catch play, just messing around. Pretty much everybody does that during catch play. It’s when you test out new things that you’re feeling or whatnot. I just happened to run into it during my rehab last year when I really had to focus on making every catch play worth it because I couldn’t just go out and throw as long as I wanted to at that point in time. It was definitely something I kind of zeroed in on, and then kind of just built on it through the offseason, kept solidifying it, and making sure it was the real deal, and obviously, a little bit of another tweak happened in the spring this year. Overall, it’s always been my most feel pitch. But even still, it’s a work in progress. Anything to make a pitch better, I’m interested in.
What exactly was that spring tweak?
It was a little bit different positioning of the ring finger on one of the seams in the front of the ball, so it just gives me a little bit even more ball security to not baby the pitch and really just rip it through the zone with as much intent as the fastball. Part of the reason why it’s so successful, I think, is because of the sell of arm speed. I try to keep it the exact same as the fastball until it’s at the plate.
Just looking at your Statcast data, all three of your secondary pitches have had a lot of successes, but you’ve struggled with your fastball, both last season and this one. Why do you think that is?
I think as a pitcher, individually speaking, I tunnel all my pitches very well. In the past, I’ve definitely thrown harder velo-wise with the fastball and gotten much better results. That’s always just been something I kind of fiddle with, and it’ll probably be something I address in the offseason to get some of that velo back, but I think the tunneling is probably the biggest thing. Guys think it’s that four-seam heater, and then I have the curveball, I have a changeup that fades off, and the slider especially holds the same line as my fastball very well until the late break on it. Then the damage on the heater, I think honestly, has come from bad locations more so than the pitch itself, and that was something that we talked about with the pitching coaches and addressed this year is that, yes, the usage is down, but when I use it, I’m using it more effectively this year. It’s been hit a couple of times, but overall, my goal with it this year is to not really try to change it. I got what I got this year right now.
Obviously, the other offspeed pitches, I think, are all better than last year. That’s definitely an added benefit, so the limited usage that I’m using the heater in right now, just to be better with locating it, which I think that’s just the normal progression of a starting pitcher in the big leagues. You’ve just got to find the places to get better every year, and I think one of mine is definitely not so much fastball command, but just the execution. That’s part of the reason why I started adding in a one-seam as well to give kind of a different look to the heater, so in heater counts, not only can they not sit on the offspeed, they can’t sit on a straight heater anymore, so that’s definitely something that’s kind of been trickling into the usage pattern right now.
What does the one-seamer add for you?
It’s actually just another word for a two-seamer. But it’s not a traditional grip to a two-seam that guys will normally throw. It’s called a one seam because when it spins, you only really see one seam and because of the patterning of that and the bald spots on the side of the ball or where you spin, it will cause it to sink and drop and less run, and it’s late. It’s almost the same speed as my four-seam, but it has the two-seam profile.
Tunneling and spin rate have obviously become ingrained in modern pitching terminology. How did you come to have an interest and understanding in these types of concepts?
It probably was introduced first to me when I got to the Orioles. A little bit with the Braves. They were definitely ahead of the Orioles at the time when I was traded. But probably spring training of 2019, that was the first time when they approached me about going to a four-seam, explaining why, with the spin rate and the axis I throw it at and everything, and then from then on, it was kind of just a progressive education on analytics of pitching.