Twins Bolster Their Rotation With Tyler Mahle

© David Kohl-USA TODAY Sports

Even in an era when starting workloads are shrinking, it’s tough to win a division title without a decent rotation. The Twins have been trying their level best to do so nonetheless, entering Tuesday with 54-48 record and a one-game division lead over the Guardians (53-49) and a three-game lead over the White Sox (51-51) despite a rotation that’s been the weakest of the three. In advance of the trade deadline, they moved to fix that, acquiring righty Tyler Mahle from the Reds in exchange for a trio of prospects.

Mahle was considered one of the top starters available at the deadline, arguably the top one after the trades of Luis Castillo and Frankie Montas in what was admittedly a thin class. There was no pending free agent anywhere close to the caliber of last year’s Max Scherzer or 2017’s Yu Darvish, while the Giants opted not to trade Carlos Rodón and the Marlins decided to hold on to Pablo López. What made Mahle enticing wasn’t just his performance but his cost, as he’s making just $5.2 million this year, and has one more year of arbitration eligibility remaining.

Hence the three-prospect package, though none of the players acquired currently rank among our Top 100 on The Board, unlike shortstop Noelvi Marte, whom the Reds acquired from the Mariners in the Castillo trade, or Ken Waldichuk and Luis Medina, whom the A’s acquired from the Yankees in the Montas deal. The full trade sends the 27-year-old Mahle to the Twins for 21-year-old lefty Steve Hajjar, 22-year-old infielder Christian Encarnacion-Strand, and 24-year-old infielder Spencer Steer.

Mahle is carrying a 4.40 ERA, higher than all of the Twins’ regular starters save for Dylan Bundy (5.04), but the underlying data illustrates that he’s pitched much better than that. The Reds’ defense — which ranks 27th in the majors with -27 DRS, 25th with a .685 defensive efficiency, and 23rd with -9 RAA — has cost him some runs. Mahle’s 3.60 FIP is better than every Twins starter except for Sonny Gray (3.41), while his 3.22 xERA outclasses all of the Twins’ starters and ranks 11th among NL qualifiers. His +1.18 runs-per-nine gap between his ERA and xERA is second in the majors behind only his new teammate:

ERA – xERA Differential Leaders
Player Team BIP BA xBA SLG xSLG wOBA xwOBA ERA xERA Diff
Dylan Bundy Twins 291 .271 .250 .458 .401 .328 .301 5.04 3.72 1.32
Tyler Mahle Reds 285 .232 .206 .389 .332 .302 .281 4.40 3.22 1.18
Austin Gomber Rockies 305 .288 .277 .489 .447 .354 .338 5.80 4.80 1.00
Trevor Rogers Marlins 271 .283 .263 .469 .422 .361 .342 5.85 4.93 0.92
Hunter Greene Reds 266 .237 .228 .463 .422 .338 .323 5.26 4.34 0.92
Patrick Corbin Nationals 379 .326 .292 .514 .489 .386 .366 6.57 5.78 0.79
Ian Anderson Braves 305 .262 .254 .407 .378 .332 .322 4.99 4.31 0.68
Chris Bassitt Mets 316 .227 .216 .371 .354 .292 .282 3.83 3.24 0.59
Lucas Giolito White Sox 273 .284 .253 .493 .425 .360 .330 5.14 4.55 0.59
Josiah Gray Nationals 269 .230 .212 .460 .410 .335 .313 4.59 4.05 0.54
Germán Márquez Rockies 367 .274 .267 .478 .443 .349 .337 5.29 4.77 0.52
Luis Garcia Astros 287 .208 .212 .395 .372 .288 .285 3.81 3.31 0.50
Robbie Ray Mariners 319 .230 .224 .431 .374 .319 .297 4.11 3.62 0.49
Aaron Nola Phillies 363 .218 .208 .363 .353 .268 .261 3.25 2.76 0.48
Alex Wood Giants 290 .253 .246 .383 .379 .300 .299 4.11 3.67 0.44
SOURCE: Baseball Savant
Minimum 250 batted ball events.

Mahle’s 26-point AVG – xBA gap is fifth among the same group, while his 57-point SLG – xSLG gap is tied for second with Bundy and Ray. Meanwhile, his raw Statcast numbers (88.3 mph average exit velocity, 6.7% barrel rate, 37.2% hard-hit rate) are good-not-great, ranging from the 55th to the 64th percentile, but more impressive is his 25.9% strikeout rate, which is seventh among qualified NL starters and helps to offset his 9.8% walk rate and 1.04 per nine home run rate.

Mahle, who last year pitched to a 3.75 ERA and 3.80 FIP with a 27.7% strikeout rate in 180 innings, has evolved into a solid mid-rotation starter thanks in large part to the improvement of his four-seam fastball. A seventh-round 2013 pick out of an Orange County high school, he took his lumps in his first three seasons in the majors, posting a 4.88 ERA and 4.86 FIP from 2017-19. He improved his fastball velocity and spin rate before the 2020 season, coinciding with the addition of Driveline founder Kyle Boddy as the Reds’ Director of Pitching Initiatives; the gains made the pitch more effective, particularly when he worked in the upper third of the strike zone and higher:

Tyler Mahle’s Improved Four-Seam Fastball
Seasons Location % Velo Spin AVG xBA SLG xSLG wOBA xwOBA
2017-19 All 61.3% 92.8 2146 .263 .244 .427 .397 .335 .320
2020-22 All 52.8% 93.8 2331 .221 .196 .412 .343 .321 .293
2017-19 Upper 35.3% 92.9 2151 .215 .196 .334 .298 .296 .281
2020-22 Upper 31.6% 93.9 2327 .178 .153 .306 .259 .287 .267
SOURCE: Baseball Savant
All = Gameday Zones 1-14. Upper = Zones 1, 2, 3, 11, and 14.

Mahle’s drop in spin rate was one of the majors’ largest in the immediate aftermath of the crackdown on grip-aiding substances in July 2021, but over the course of his full seasons, the decline isn’t as steep, falling from an average of 2,388 rpm in 2020 to 2,336 in ’21 to 2,294 this year. That still places him in the 70th percentile according to Statcast.

The improved fastball wasn’t Mahle’s only change before the 2020 season; he ditched his changeup and curveball in favor of a splitter and cutter. He’s throwing those two pitches more this year than last, at the expense of his slider, which has been hit for a .304 AVG and .413 SLG this year and .266 AVG/.451 SLG last year.

Mahle joins a rotation that after losing Kenta Maeda to Tommy John surgery ranked 20th in our preseason Positional Power Rankings and has more or less lived up to that billing. The unit’s 4.19 ERA ranks ninth in the AL, their 4.24 FIP and 5.7 FIP both 10th, and their 492.1 innings 13th. Gray (3.41 ERA, 3.41 FIP) has been very good, but he’s the only one of the regular starters (Bundy, Joe Ryan, Chris Archer, and Devin Smeltzer being the others) with a FIP- below 100, and of that group, only Ryan has has an ERA- below 100 (97, via a 3.78 mark). Smeltzer (4.02 ERA, 5.49 FIP in 12 starts) was optioned to Triple-A during the All-Star break and Bailey Ober (4.01 ERA, .79 FIP in seven starts) is on the 60-day injured list with a recurrent groin strain; he isn’t expected to return until late August. Opening Day acquisition Chris Paddack is out for the year due to Tommy John surgery as well.

As for the prospects, Steer is the most advanced, a third-round 2019 pick out of the University of Oregon who was hitting .242/.345/.485 (118 wRC+) with 12 homers for the Twins’ Triple-A St. Paul affiliate. Listed at 5-foot-11, 185 pounds, Steer entered the year ranked 16th on the Twins’ top prospects list as a 40+ FV prospect but had risen to eighth due to graduations and his own performance. From Eric Longehagen’s notes:

Steer is a bat-first infield prospect who can really barrel fastballs. Per Synergy Sports, he’s hitting .297/.402/.529 against them this year, doing most of his home run damage to his dead pull side against heaters located in the meat of the plate. He’s a shift-aided defensive player, heavy footed and relatively unathletic, the sort who you hope will play passable second base and might be better suited at the corners. Where he fits on defense will dictate his ceiling, but his bat will enable him to play a significant big league role even if he tumbles down the spectrum.

Encarnacion-Strand, who lists at 6 feet and 224 pounds, is a fourth-round 2021 pick out of Oklahoma State who tore it up at High-A Cedar Rapids (.296/.370/.599, 20 HR, 161 wRC+, 330 PA) and then Double-A Wichita (.333/.400/.685, 5 HR, 60 PA, 167 wRC+). He was only an honorable mention on that March prospect list, a situation that Eric explained:

Encarnacion-Strand has outperformed the expectations I set for him upon scouting him in junior college and at Oklahoma State. He clubbed 20 homers in 74 High-A games en route to a debut season promotion to Double-A, where some of his breaking ball chase issues from college have started to be exploited by opposing pitchers. Built like a hard-hitting NFL safety, Encarnacion-Strand has thunderous raw power and has made himself into a viable third base defender, though he’s still a little stiff over there. The risk of him moving to first base and ending up with below-average contact ability create some Quad-A risk here, but Encarnacion-Strand’s median outcome is that of a power-hitting corner role player and he’ll be added to the 40 FV tier of The Board.

Hajjar is a 6-foot-5, 245-pound lefty who was chosen in the second round of the 2021 draft out of the University of Michigan; he ranked 23rd in the system entering the season as a 40 FV, and moved up to 22nd as the season progressed. He’s spent most of the season at A-level Fort Myers save for one rehab start with the team’s Complex League affiliate after missing five weeks due to a shoulder strain. At Fort Myers, he pitched to a 2.47 ERA and 2.81 FIP while striking out 40.8% of all hitters. Via Eric, again:

Hajjar was a young-for-the-class college pitching prospect out of Michigan who has been dominant against Low-A hitters this year, and was probably a level too low for his skill set. He dealt with injury in June but his velocity was fine in his most recent start (up to 94 mph) and his stuff appears intact. While drafted out of college, Hajjar is still more of a developmental prospect tracking like a back-of-the rotation type right now, though he has a chance to pop if he can throw harder. His low-90s fastball has riding life that makes it playable at the letters, he has feel for a slider and changeup that are both consistently average or better (though neither is dominant), and you can project on elements of Hajjar’s skill set in the abstract because he’s put together great, has a smooth, elegant delivery, was young for his draft class, and lost crucial reps due to the pandemic.

Like Mahle, Castillo and Montas were each traded while having a year of club control remaining. The three have performed similarly over the past two or three seasons, with most of the difference being Mahle’s lack of defensive support elevating his ERA a bit; he has missed the most bats of the trio. All three have dealt with minor shoulder issues this season; Castillo missed all of spring training with shoulder soreness and didn’t debut until May 9, while Mahle and Montas each missed a couple of turns in July with a mild shoulder strains. If the trio of prospects the Reds are getting hre looks light compared to the returns for the other two, this non-prospect-oriented scribe and his prospect-expert colleague agree. “Even if you think I’m light on Steer and that he should be on the offseason Top 100 as a 50 FV prospect, that’s still just one guy like that as opposed to two like the other deals,” Eric wrote, referring to the aforementioned Top 100 prospects and the high-risk/high-reward Edwin Arroyo, an 18-year-old Low-A shortstop in the Castillo trade.

‘Tis the season for such debates, and it will be awhile before we can truly compare the hauls of the A’s and Reds for those starters. What’s known now is that Minnesota’s rotation is in significantly better shape than it was 24 hours ago, both for this year and next, and with the deadline additions of relievers Michael Fulmer and Jorge López while the Guardians and White Sox more or less sat on their hands (the former traded Sandy Léon… to the Twins, while the latter acquired Jake Diekman from the Red Sox on Monday), the AL Central flag is theirs for the taking.

Brooklyn-based Jay Jaffe is a senior writer for FanGraphs, the author of The Cooperstown Casebook (Thomas Dunne Books, 2017) and the creator of the JAWS (Jaffe WAR Score) metric for Hall of Fame analysis. He founded the Futility Infielder website (2001), was a columnist for Baseball Prospectus (2005-2012) and a contributing writer for Sports Illustrated (2012-2018). He has been a recurring guest on MLB Network and a member of the BBWAA since 2011, and a Hall of Fame voter since 2021. Follow him on Twitter @jay_jaffe... and BlueSky

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1 year ago

I think this might be the single best deal a contender made at the deadline this year. Mahle cost something like a 1/3rd of the prospect value that Montas did, and probably 1/5th of what it cost to land Castillo. And instead of getting a 3.5+ win starter they get a 3+ win one. And he’s younger so he’s a possible extension candidate.

I do think that all three of the guys sent back are interesting prospects but it’s not anywhere on the same level as the other deals.

1 year ago
Reply to  sadtrombone

Yeah, this one looks really good for the Twins compared to the other two.