The Rangers Rotation Has Been Great, but Things Are Gettin’ Weird

Way, way, way back in December 2023, the Rangers signed Tyler Mahle to a two-year contract. Absolutely nobody cared at the time, mostly because the news dropped the same day as Shohei Ohtani’s first press conference with the Dodgers. But also because Mahle, then recovering from Tommy John surgery, was expected to play a trivial part, at best, in the 2024 season.

Mahle had been a bit of a hipster favorite as an upper-mid-rotation starter in Cincinnati and then briefly in Minnesota — far from a household name, but from 2020 to 2022, he’d been quite good, and in high volume. Over those three seasons, he’d averaged 27 starts, 146 innings, and 3.0 WAR per 162 team games, with an ERA- of 90. For two years and $22 million, the Rangers were conceding that he’d rehab on their dime for most of 2024. But he would’ve been available for the 2024 playoffs if they’d made it that far, and if everything worked according to plan, they’d have a workhorse no. 3 starter under contract for 2025 at a fraction of what that kind of production usually goes for.

At least in 2025, everything has been working according to plan. Mahle has made 11 starts so far this season, with the past 10 lasting at least 80 pitches and five innings. Until his most recent outing, he hadn’t allowed more than two runs in any start. Even then, he allowed only three runs in his season-worst outlier. His 1.80 ERA is fifth best among all qualified starters.

If you want to declare victory for the Rangers now, because Mahle has been great so far this year and the signing looks like the kind of bargain you’d be embarrassed to tell you friends about because they’d think less of you for ripping off that old guy at the yard sale who didn’t know what he had, feel free to stop reading.

For everyone else, take a look at Mahle’s strikeout numbers: just 6.45 K/9 and a K% of 18.3%, both well below average. And he’s not pounding the zone and letting the chips fall where they may, either. He’s still walking guys. Mahle’s K-BB% is just 9.4%, the 16th lowest out of 79 qualified pitchers.

Good pitchers can have a strikeout rate that low, but not great ones. As of this writing, there are 18 qualified starters with a single-digit K-BB%; 12 have an ERA below 4.00. But Mahle is the only one with an ERA even below 3.00, let alone 2.00.

Even in the early 2020s, Mahle wasn’t exactly J.R. Richard, so if he isn’t racking up strikeouts, that’s not in and of itself cause for concern. But if you look over at the stats we traditionally use to judge flukiness, Mahle’s line lights up like the winning spin on a slot machine.

Back in the early 2010s, you could get an entire blog post out of a starter having a good ERA but a low BABIP, so watch out for that regression monster. We have a better understanding of how pitchers control quality of contact now, and much more sophisticated tools. Mahle’s fastball velocity leaves something to be desired, but he has terrific carry on his four-seamer, a slider that he can dot on the outside corner to righties like it’s on rails, and a splitter and cutter that he can use to keep opponents guessing. I can see some potential for weak contact in here.

But those fancy tools aren’t too optimistic either. Mahle is outperforming his xERA by more than two runs, and his xwOBA by 82 points. Out of 209 pitchers who have faced 100 or more batters, Mahle is the third-biggest overperformer by wOBA-xwOBA, and the sixth biggest by ERA-xERA.

This is not especially interesting to me. It’s May. Some pitcher or other always has an ERA that’s half what his peripherals say it ought to be. It might as well be Mahle as anyone else.

What’s interesting to me is that the entire Rangers rotation is like this.

Texas came into this season with fairly high expectations. Our playoff odds gave the Rangers about a one-in-four chance of winning the AL West, and about even odds of making the postseason. Our staff predictions were more bullish: 12 writers out of 26 picked Texas to win the AL West, the most of any team, and 21 out of 26 had the Rangers in the playoffs. I was one of them; I had the Rangers not only winning the division but the pennant as well.

So while Texas is by no means out of the running now, suffice it to say they hoped to come out of Memorial Day on the other side of .500. But the offense has been unproductive; Marcus Semien and Joc Pederson have been unspeakably awful. Jake Burger has been up and down, Leody Taveras straight-up got waived, Evan Carter remains lost at sea. The bullpen has been downright treacherous.

But the Rangers rotation has been terrific. Texas is one of just two teams this season whose starters have a collective ERA under 3.00. They’re first, by nearly three quarters of a win, in WPA. They’re ninth in batters faced per start.

But the rotation as a whole is also outperforming its FIP by more than two-thirds of a run. That’s the third-highest positive discrepancy in the league. Rangers starters are allowing a .277 wOBA but a .323 xwOBA; starters as a whole are currently coming in 15 points under their expected wOBA league-wide, but the Rangers’ overperformance is the biggest of all 30 teams. The Rangers have only used six starting pitchers so far this year — which is itself a good omen, even this early in the season — but they’re all contributing to this phenomenon.

It’s hard not to think about this through the lens of Jacob deGrom’s rebirth as a finesse pitcher. Michael Rosen wrote about this a few weeks ago under the headline “Jacob deGrom, Command God.” (Said headline gets very interesting if you interpret the second half as an imperative rather than a modifier.)

We knew all along that deGrom had plus-plus command, but when he was throwing 102 mph and striking out 40% of opponents, that sort of thing got left below the fold. Now, deGrom turns 37 next month, and he’s trying for his first 100-inning season since 2019; he’s letting off the gas a little in order to put off that next catastrophic injury. In fact, on Sunday deGrom achieved a career first: He started a game and didn’t strike anyone out. Never before in 229 major league outings had he achieved such a feat, even when he was lifted early due to injury.

I wondered if maybe the same thing was happening to the other Rangers pitchers. Rocker’s contributions this year have been limited, but Leiter has made eight starts; and in those eight starts, he’s struck out just 30 batters in 41 innings. Those of us who remember Leiter’s draft year at Vanderbilt would be astonished by this development; in 2021, he struck out 179 batters in 110 starts. Even in 2023 and 2024, Leiter was running strikeout rates in the 30s in Triple-A.

But as far as Texas’ veteran starters are concerned, it’s a mixed bag in terms of strikeout rate. Mahle’s strikeout rate has plummeted from his career norm, as has deGrom’s. But Eovaldi has been rock steady, and Corbin… well, he’s just spent five years as the subject of a science fiction novella about a futuristic criminal justice punishment that somehow goes horribly wrong, which is meant to inspire contemporary American readers to consider the failings of our own prison system. I’m not sure how much there is to be gleaned from comparing this Corbin to that one.

So I don’t think there’s a staff-wide directive to avoid strikeouts (insofar as that were ever a plausible explanation). On a pitch-by-pitch basis, Rangers starters are in the back half of the top 10 in the league in Zone%, chase rate, in-zone contact rate, and overall contact rate. They’re 11th in GB/FB ratio, 16th in line drive rate, 15th in Barrel%, and fourth in HardHit%.

All of this is to say: This looks like a good starting rotation. Not only that, but a fairly deep one. Eovaldi, deGrom, and Mahle are a playoff-quality 1, 2, and 3, and if at least one of Corbin or Leiter can keep piling up innings behind that trio, so much the better.

And that’s what FIP sees them as. When I talk about regression, I don’t mean that Mahle’s going to start giving up eight runs a start to bring the universe into balance; I mean that he’s probably a pitcher who’ll put up an ERA in the mid-to-high 3.00s. Which is what he was with Cincinnati.

But all that makes for, oh, a top-10 rotation in baseball, rather than a top-two one. And given that the Rangers are floating around .500 even with this gift from their starters, this is a sign that their offense needs to get back into shape sooner rather than later.