Mike Baumann is coming into his own as a reliever

After years of fringiness as a starting pitcher, a relief role is really allowing Big Mike’s fastball and curveball to shine.

These days, it’s worth pausing a bit to show some gratitude for the Orioles, and especially for their late-inning pitching. The O’s own the second-best record in the American League, and a large part of that is thanks to the bullpen, one of the best in the game right now. The Orioles’ bullpen is ranked first in WAR, second in ERA, third in strikeouts, fourth (tied) in WHIP, and first in adjusted ERA.

As for the top individual performers, it’s a crowded field. From top down, based on adjusted ERA, you have the otherworldly Yennier Cano, the towering Félix Bautista, the flamethrowing Bryan Baker, the confounding Danny Coulombe—and then, Mike Baumann.

This is a nice development, because a little less than a year ago it wasn’t clear where, or even if, Mike Baumann had a role on this team. In 2022, Baumann was still a hybrid starter/long-reliever type, but not a particularly trusted one. In April of that year, the Orioles tried using him out of the pen, but he finished with a 6.14 ERA in five appearances. Baumann got optioned at the end of the month when Kyle Bradish made his starter debut, and only in September did he get called up to the majors for another extended stretch. Overall, he pitched to a 4.78 ERA in 13 appearances, didn’t strike out many hitters (6.0 K/9) and allowed a .314 opposing average against.

After the 2022 season ended, CC’s Stacey concluded:

Given the chance to prove himself as a big leaguer, he failed…sort of. He made six appearances [in April and May], four of which were starts, and they were just blah. That’s a technical term.

Based on what we’ve seen so far, it’s hard to imagine a future for Baumann that is anything more than being an up-and-down guy in 2023 followed by being either passed through waivers to spend more time at Norfolk, or possibly claimed on waivers by a team that hopes they can do better with the large-framed baseball man.

In other words:

This was a fair assessment—it seemed like Baumann might end up one of those fringey rotation types who gets squeezed as the talent around him gets better. Baumann has always had power pitcher potential, but the question was, in what role? Drafted in the third round of the 2017 draft, the big righty was highly thought of enough as a starter prospect that as recently as 2022 he ranked No. 13 on CC’s composite list. But he struggled to find consistency in this role, with a 5.40 career ERA as a starter and a 1.582 WHIP.

This season is the first that Baumann has been a full-time reliever, and it’s definitely putting him in his best light. He’s got a 3.27 ERA in 22 innings, and if you took out a pair of one-inning clunkers, that’d be 0.90. Opponents are hitting .184 against him and his strikeout rate is 9.8 per nine innings, a nearly 4-point improvement on his 2021 and 2022 seasons.

What’s changed? A lot, actually. Baumann has changed his wind-up, simplified his offerings, and upped his velocity.

Here is Baumann in 2022, with a diminutive leg kick and throwing from a pretty pure overhead angle.

Now here he is in 2023, with a very slight sidearm angle and a larger kick. I presume the arm angle has to do with generating more spin. As for the leg kick, it could be to generate more power, or to help Baumann to sync up his wind-up a bit better. If the former, so far so good: his fastball velocity is up 2 mph from two seasons ago. If the latter, mixed results for now: Baumann’s walks are up nearly 50% from last to 4.5 BB/9, but he is also throwing more first-pitch strikes than ever before.

The story plays out, too, in results. Well, one result in particular, and this is the one that matters above all: he’s striking out more hitters. Since last season, Baumann’s strikeout percentage is up 12% and his whiff rate is up by 8%.

His stuff is looking better in all senses, too. He’s throwing fewer sliders and sinkers than he did, and why not? His fastball and curveball, now his primary pitches, have an expected average of .189 and .146. As noted, the fastball velo is up, and he’s got a nice 24% whiff rate on the pitch. Run value tells the same story: in 2022, Baumann’s fastball was an average pitch (0 RV) but now it’s a weapon (-3 RV).

Same deal with the curveball: its spin rate is up by over 100 rotations per minute, and his whiff rate on the pitch has more than tripled in a year, from 12.8% to 42.1%.

Perhaps similar to what the Orioles did with Jorge López, turning Baumann into a reliever has afforded him the freedom to focus on what he does best: launching heaters with abandon, while dotting in enough curveballs to make things interesting.

It’s fun to see Big Mike out there slinging it with confidence these days, and to see Orioles manager Brandon Hyde trusting the big right-hander in high-leverage late-inning situations. The truth is, Baumann has made sufficient strides as a pitcher that he deserves to feel confident.