Todd's Takes: Testing an Old Hypothesis and the Exploits of New Players

Todd's Takes: Testing an Old Hypothesis and the Exploits of New Players

This article is part of our Todd's Takes series.

Two Faced

I have long considered every starting pitcher as two different hurlers: Windup Guy and Stretch Guy. The notion was rekindled while watching Kyle Muller's start over the weekend. I've been stashing him on my Tout Wars reserve, so I've been tracking his performance for Triple-A Gwinnett. In Tout Wars, we can activate players after the initial lineup lock is they've subsequently been promoted or taken off the IL, with the caveat the player we're replacing must be released. I waived goodbye to Sam Long and activated Muller.

He cruised through three innings, then gave up his first hit in the fourth as Miguel Rojas singled. Maybe it was because I wanted it to fit my agenda, but Muller didn't look as confident working from the stretch, and BOOM, Jesus Aguilar took him deep.

I don't want to make this about Muller, but watching triggered some old thoughts. I've always wanted to research my two-guy theory, but no one tracks pitches thrown from the windup versus stretch. In the past, I've parsed the data as follows:

Windup

  • Bases Empty

Stretch

  • Runner on First
  • Runner on Second
  • Runners on First and Second
  • Runners on First and Third

Unknown

  • Runner on Third
  • Runners on Second and Third
  • Bases Loaded

Complicating matters is the fact that most relievers pitch exclusively from the stretch, while some starters have also eschewed the windup. Further, many openers are classified as starters but they're ostensibly relievers while most bulk relievers are essentially starters.

There is

Two Faced

I have long considered every starting pitcher as two different hurlers: Windup Guy and Stretch Guy. The notion was rekindled while watching Kyle Muller's start over the weekend. I've been stashing him on my Tout Wars reserve, so I've been tracking his performance for Triple-A Gwinnett. In Tout Wars, we can activate players after the initial lineup lock is they've subsequently been promoted or taken off the IL, with the caveat the player we're replacing must be released. I waived goodbye to Sam Long and activated Muller.

He cruised through three innings, then gave up his first hit in the fourth as Miguel Rojas singled. Maybe it was because I wanted it to fit my agenda, but Muller didn't look as confident working from the stretch, and BOOM, Jesus Aguilar took him deep.

I don't want to make this about Muller, but watching triggered some old thoughts. I've always wanted to research my two-guy theory, but no one tracks pitches thrown from the windup versus stretch. In the past, I've parsed the data as follows:

Windup

  • Bases Empty

Stretch

  • Runner on First
  • Runner on Second
  • Runners on First and Second
  • Runners on First and Third

Unknown

  • Runner on Third
  • Runners on Second and Third
  • Bases Loaded

Complicating matters is the fact that most relievers pitch exclusively from the stretch, while some starters have also eschewed the windup. Further, many openers are classified as starters but they're ostensibly relievers while most bulk relievers are essentially starters.

There is a practical, if not pragmatic application of this hypothesis. The premise is pitchers' skills decline a bit from the stretch. If they didn't, why even use the windup? As such, if he's been snake bitten on hit rate, the pitcher will be forced to work from the stretch, where he's less effective. His bad luck gets embellished. It could even be that his control was off, so not only is he dealing with that, he's also thrust into going from the stretch. In either case, because the pitcher has been throwing from the stretch, his skills could suffer and register lower than his true level. Of course, his true level is a weighted average of windup versus stretch, but these two examples inflate the stretch component.

In addition, expected stats (xERA, xFIP, FIP, SIERA, etc.) bunch everything to suggest what should have happened. One of the tenets of analysis is identifying arms likely to regress, both good and bad. I'm convinced the delta between actual ERA and any of the estimators is in part from the difference between windup guy and stretch guy. Specifically, if windup guy and stretch guy are close to the same pitcher, he should be able to "outpitch his peripherals." He's not really outpitching them; the expected ERA formulas assume his skills are further apart. The opposite should also be true. If the pitcher exhibits disproportionately worse skills from the stretch, his ERA estimators could give the impression he's been unlucky, but the truth is he's much less effective from the stretch.

As has been mentioned, the data to look at this conundrum is already sketchy. Breaking it into windup guy and stretch guy adds the additional layer of variance, since smaller samples are subject to wider error bars.

Even so, it's been awhile since I gathered the data, so I decided to do a refresh. Plus, even though the pitches aren't explicitly captured as windup or stretch, there are more means to filter and hopefully refine the results.

Here are some 2022 numbers, through August 16. They're presented for starters and relievers from the seventh inning on. Pruning out openers isn't worth the effort, but looking at reliever data starting in the seventh should minimize bulk reliever innings.

Starting Pitcher

DeliveryBFBAK%BB%HR%BABIPwOBAFIPxFIP
Windup459100.24222.3%7.3%3.0%0.2880.3064.034.25
Stretch268310.25920.0%7.7%3.1%0.2990.3224.244.47
Unknown42670.25721.0%9.6%2.6%0.2830.3094.224.66

Reliever

DeliveryBFBAK%BB%HR%BABIPwOBAFIPxFIP
Windup212700.22325.3%8.3%2.5%0.2810.2883.644.00
Stretch150710.24222.3%9.4%2.6%0.2930.3074.054.36
Unknown30810.27122.8%12.7%2.4%0.3160.3204.464.83

To be clear, relievers are almost all working from the stretch so in the interest of adding even more confusing text to the columns, please consider windup, stretch and unknown to be designated as shown above.

Sure enough, by every measure, starting pitcher's skills and the ensuing outcome (measured by wOBA) suffer when utilizing the stretch. However, this is the first time I've parsed out reliever data, and their numbers also decline. This suggests it's not the delivery, but rather the fact that runners are on base.

Hmm.

If the loss in effectiveness is from how the ball is delivered, the velocity and spin rates of specific pitches should be lower from the stretch, right? Let's take a look.

  • 4S: Four-seam fastball
  • 2S:Two-seam fastball/sinker
  • SL: Slider
  • CV: Curveball

Starting Pitcher

Delivery4S pitches4S Vel4S Spin2S pitches2S Vel2S SpinSL pitchesSL VelSL SpinCV pitchesCV VelCV Spin
Windup6134593.52259.12657592.62124.83086184.72389.82211278.82499.2
Stretch3180993.62256.31587092.72125.91953384.92388.91175678.92516.6
Unknown696193.92269.5340093.12126.6453285.22393.8276179.42529.4

Reliever

Delivery4S pitches4S Vel4S Spin2S pitches2S Vel2S SpinSL pitchesSL VelSL SpinCV pitchesCV VelCV Spin
Windup2958094.22282.41360994.32153.22085984.52448669080.52530.3
Stretch1918394.02281.8971794.32158.11516584.52464.8443080.72533.6
Unknown348293.92275.1178094.72166290284.62466.786981.32511.9

The same disclaimer applies to relievers; their deliveries are almost all from the windup, so think of this in terms of on-base scenarios. 

It's evident my intuition has been wrong for over 20 years. At least via velocity and spin, there is no discernable difference between pitch quality from the windup and stretch. Of course, there are other means of measurement such as movement, but on the surface there appears to be other reasons why a starting pitcher is less effective from the stretch. 

Defensive positioning could account for BABIP, but not strikeout, walk and home run rates. Pitch sequencing could be different. The ball could be harder to pick up from the windup or perhaps tunneling is more effective. Pitchers' arsenals could be more predictable with runners on or maybe it's easier to pick up tipping of pitches. 

While it's a bummer, it appears the quality of a pitch delivered from the windup and stretch are the same, so there has to be a different reason (or reasons) for the decrease in performance with runners on base. Unearthing could help separate luck from skill.

Looks like I have another offseason project.

Box Score Blitz

  • CIN 1, PHI 0: Nick Lodolo and Ranger Suarez both threw seven scoreless innings, fanning eight with two walks. For Lodolo, it was a welcome rebound from a shaky outing in the Field of Dreams game. For Suarez, it was a continuation of some solid pitching, as he's now sporting a 1.02 ERA and 0.91 WHIP with 33 strikeouts to only eight walks over his last six starts, spanning 35.1 innings. Since the Phillies acquired David Robertson, Seranthony Dominguez has collected three saves with Robertson notching a pair. Usage patterns favor Dominguez as the primary closer, but he likely won't garner all the saves.
  • CHC 3, WSH 2: With his 2-for-4 effort, Franmil Reyes has hit safely in each of the seven games he's played in a Cubs uniform, posting a .367/.367/.733 line with a reasonable 23 percent strikeout rate in this span. There is a good chance Reyes would have gone on a similar streak with the Guardians. Jumping on the bandwagon is fine, but brace for a reversion to Reyes' high strikeout form. That said, if the landing is close to the season-long .250/30 HR hitter expected, that'll play. It was an odd outing for Drew Smyly as he threw 100 pitches with 69 for strikes (a high percentage), yet lasted only 5.1 innings despite striking out only four with no walks. The Nationals worked the count, but it didn't pay off with free passes. Still, Smyly did his job, keeping the Cubs in the game. Rowan Wick claimed his eighth save, getting back on track after allowing homers to Luke Voit and Lane Thomas the prior evening.
  • MIN 4, KC 0: The Twins winning was secondary to Tyler Mahle exiting the tilt in the third inning due to shoulder soreness. His velocity was markedly down, but he managed to hurl 2.1 scoreless stanzas before leaving. Mahle is slated for an MRI. As always, our top-notch notes team will have the update posted as soon as it's available. Jose Miranda provided all the offense the Twins needed with a first-inning homer. As has been documented a few times, Miranda has been crushing the ball since the break. 
  • TOR 6, BAL 1: After Austin Voth and Ross Stripling pitched exceptionally well, the Blue Jays got to the normally reliable Orioles bullpen to grab an important win as both clubs are vying for one of the three AL wild card berths. Voth has quietly entered the streaming realm with his last four starts registering a 2.11 ERA and 0.84 WHIP with a respectable 19 punch outs in 21.1 frames. Stripling displayed no ill effects from the hip woes shelving him since July 30.
  • SEA 11, LAA 7: I was watching with the sound down, but I could imagine the announcers lauding George Kirby for battling without his best stuff. Sure, it was true, but he was facing a depleted Angels lineup while his mates were able to punish a couple of Halos hurlers clearly taking one for the team. Don't get me wrong, this isn't a knock on Kirby, as he's one of my favorite young pitchers. Wednesday was one of those days for Julio Rodriguez as he posted an 0-for-5 while the Mariners put up 11 runs. Rodriguez was the fourth overall pick in a 2023 NFBC Draft Champions league. I guess this means the Premature Edraftulation League is no longer the first official NFBC league drafted each year. Though, we will finish a couple weeks after the season ends (we start during the final series of the regular season) thus we'll be the first draft to finish, so there's that. This is the league I co-manage with Derek VanRiper and we're currently a couple points out of first with just one point in saves. It wasn't by design, but it's been a fun challenge trying to compensate.
  • SD 10, MIA 3: A first inning Jake Cronenworth grand slam helped fuel an early 5-0 lead for the Padres. Even with the cushion, Mike Clevinger could only muster 4.1 innings, needing Adrian Morejon to bail him out. Morejon was nasty, fanning three in 1.2 innings. He's yet to allow a run this month, tallying 7.2 frames with seven strikeouts. Pablo Lopez continues to struggle for the Marlins, as he's put up a 7.20 ERA and 1.53 WHIP since the break, albeit with 30 whiffs to just eight free passes in those 30 innings. He's been victimized with 38 hits (.363 BABIP), with five leaving the yard. This is usually a combination of bad luck and some mistakes. His 3.74 xFIP in this stretch suggests patience with Lopez.
  • BOS 8, PIT 3: The Red Sox continue to handle the second division teams while struggling against the iron. Enrique Hernandez's return has pushed Jarren Duran to the bench as Christian Arroyo has earned a regular lineup spot while Duran's stock has plummeted over the summer. Arroyo's 3-for-5 effort elevated his line since coming off the IL on July 30 to .390/.429/.559. Of course he won't keep it up, but with everyday playing time, Arroyo is mixed-league worthy.
  • NYY 8, TB 7 (F/10): The Rays wasted a quality start from Corey Kluber as their bullpen yielded six runs to the Yankees, including a walk-off tenth-inning grand slam from Josh Donaldson after Tampa put three points on the board to begin extras. Aroldis Chapman was awarded what could be the least deserved win of the season after surrendering two runs in two-thirds of an inning. Despite allowing the zombie runner to score, Scott Effross again pitched well for the Yankees and is a name to consider in leagues where you're looking to support ratios.
  • CLE 8, DET 4: In his second start since rejoining the Tigers rotation, Daniel Norris surprisingly outpitched Cal Quantrill, but it went for naught as the Guardians exploded for six runs in the eighth innings. Cleveland almost didn't score at all in the inning as Detroit reliever Andrew Chafin fanned the first three hitters, but the third, Luke Maile, reached on a wild pitch. Five straight hits ensued, propelling the AL Central leaders to another win. Oscar Gonzalez is slashing .350/.350/.517 since coming off the IL in early August, but he has just one homer, one steal and no walks in 15 games. However, his underlying metrics indicate his power has been artificially low, so expect increased production, which will be embellished as he's entrenched as the Guardians regular cleanup batter.
  • NYM 9, ATL 7: Max Scherzer wasn't as sharp as usual, but he still managed to fan eight Braves over 6.1 innings. Three walks helped Atlanta put up four runs against Scherzer, but it wasn't enough as the revamped Mets lineup slugged their way to a nine-spot. Leading the way was Starling Marte with a pair of long balls. He hasn't run wild like last season, but the two homers gives Marte 15 on the season, already matching his output from last year. Francisco Lindor clubbed his 21st, but the real story is Brett Baty going deep in his first MLB at bat. The lefty-swinging third baseman is one of the Mets top prospects. He'll play against righties while Luis Guillorme is out but will need to avoid the strikeout bug to be a factor over the final quarter of the season.
  • STL 5, COL 1: The Cardinals acquired Jordan Montgomery to keep them in the game while their offense chips away, and that's exactly what happened as he fanned eight Rockies in 5.2 frames. Nolan Gorman has been dropped from second to fifth in the Cardinals lineup, but in terms of average fantasy production, the two spots are a wash. What's more important is since the break, Gorman is carrying an impressive 52.6 percent hard-hit rate, boding well for production from the five-hole.   
  • OAK 7, TEX 2: Shea Langeliers cranked his first MLB homer, but he was outshined by fellow backstop Sean Murphy who left the yard twice. Langeliers and Murphy will both play a lot as Oakland will move them around to keep both in the lineup. With Elvis Andrus released, Nick Allen should see a boost in playing time. He was 0-for-5 last night, but he was leading off, which is nice.
  • HOU 3, CHW 2: Despite allowing 10 men on in seven stanzas, Framber Valdez recorded his 20th consecutive quality start. He was bailed out by three double plays along with six strikeouts. Michael Kopech also pitched well, posting his third quality start over his past four outings. Back in the spring, Jose Altuve vowed to run more. Last night, his two pilfers brought him to a dozen for the year. Sure, it's well short of his salad days, but it's just one fewer than he sniped over the past three years combined.
  • LAD 2, MIL 1: On June 16, Tony Gonsolin was sitting on a 1.58 ERA, but his estimators were all at least twice that, so regression was expected. Since, he's posted a 2.92 ERA, with similar estimators. Yes, he's been (almost as) lucky, but Gonsolin has also improved his K-BB% a couple of ticks. This is just a reminder to keep in mind that the effect of regression can be mitigated by improving skills, which Gonsolin has demonstrated. That said, Lady Luck is still on his side. It wasn't clean, but Craig Kimbrel recovered from a blown save by recording his 21st save of the year. Kimbrel should be fine for fantasy down the stretch, but the Dodgers historically handle the ninth differently in the playoffs.
  • ARI 3, SF 2: Stone Garrett joined the recent wave of callups producing right away with his 2-for-3 effort. It's only an MLE translation, but Stone has the skills for a 20/20 type season. Arizona is in audition mode, so Garrett could get a decent look down the stretch. Pretty swings leading to majestic homers usually describe lefty hitters, but J.D. Davis' swing qualifies from the right side. His defense is suspect, but even the challenging dimensions of Oracle Park can't keep Davis in the yard when he connects like he did last night. Unfortunately for Carlos Rodon and his 11 strikeouts in six innings, Davis' go ahead shot in the sixth didn't hold up, as Jake McCarthy's two-run pinch-hit single in the eighth was the game-winner.

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ABOUT THE AUTHOR
Todd Zola
Todd has been writing about fantasy baseball since 1997. He won NL Tout Wars and Mixed LABR in 2016 as well as a multi-time league winner in the National Fantasy Baseball Championship. Todd is now setting his sights even higher: The Rotowire Staff League. Lord Zola, as he's known in the industry, won the 2013 FSWA Fantasy Baseball Article of the Year award and was named the 2017 FSWA Fantasy Baseball Writer of the Year. Todd is a five-time FSWA awards finalist.
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