Before the 2026 opener, MLB counted 13 World Series pitches at 102+ mph in the tracking era, and Chapman threw ten of them.
Back to the trend of the day: Milwaukee wins first game of baseball's championship, holding off Tampa Bay
Poly Rating · from the trend of the day
Fastest Pitch in World Series History: Top 7 (2026)
The fastest pitch in World Series history, Jacob Misiorowski's 103.5 mph opener, was taken high for a ball, while Chapman's 103.2 mph record from 2016 at least got a ninth-inning out.
- No. 1: Aroldis Chapman 103.2 mph to Coco Crisp, 2016 World Series Game 2
- 7 places
01Final list
The leading AIs each built their own list of ten independently. Here is one result that is easy to check: every place has a reason, a source, and the list of AIs that included it.
Order: from most to least AI agreement.
A bright badge means this AI put the entry on its list. A dim badge means it did not.
- 1
Aroldis Chapman 103.2 mph to Coco Crisp, 2016 World Series Game 2
The record for a decade, and it got a ninth-inning groundout. Statcast says 103.2 mph, but an MLB.com 2016 story reported 104.1, so the sources disagree.
Included it: Claude, ChatGPT, Meta, Grok, Gemini, DeepSeek.In their lists: Claude: 2 · ChatGPT · Meta: 3 · Grok: 1 · Gemini: 10 · DeepSeek: 1
What each AI noted 6
- Claudeplace 2
It is the fastest tracked World Series pitch by MLB.com's count, and the Fox list leaves it out.
Source ↗ - ChatGPT
Named differently in its own list: open the full list.
- Metaplace 3
104.1 mph reported by radar gun same at-bat – shows Statcast 103.2 vs stadium gun gap that still fuels debates
Source ↗ - Grokplace 1
Ninth-inning groundout that helped lock a series-evening win, far higher leverage than a first-pitch ball
Source ↗ - Geminiplace 10
Hit 104.1 mph on the radar gun against Coco Crisp, setting what stood for a decade as the Fall Classic velocity record in a low-stress 5-1 blowout.
- DeepSeekplace 1
The fastest pitch ever to end a World Series plate appearance with an out, and it carried a 1.08% cWPA swing.
6 AIs put it here - 2
Jacob Misiorowski 103.5 mph, 2026 World Series Game 1
The fastest tracked World Series pitch, but it was the first pitch of the game, taken high for a ball by Yandy Díaz. Almost no title stakes.
Included it: Claude, ChatGPT, Meta, Grok, Gemini, DeepSeek.In their lists: Claude: 1 · ChatGPT · Meta: 2 · Grok: 2 · Gemini: 7 · DeepSeek: 2
What each AI noted 6
- Claudeplace 1
The new World Series record came on the very first pitch, and he threw 38 pitches at 100 mph or more that night, the most in a World Series game in the tracking era, and Milwaukee won 3-2.
Source ↗ - ChatGPT
Named differently in its own list: open the full list.
- Metaplace 2
103.5 mph on very first pitch of 2026 World Series – fastest ever tracked in Series, but a ball above zone with near-zero cWPA
Source ↗ - Grokplace 2
Record speed on the opening pitch of the Fall Classic, taken for a ball with zero count leverage
Source ↗ - Geminiplace 7
Set the all-time World Series velocity record at 103.5 mph to punch out Yandy Díaz, establishing psychological dominance in a Game 1 duel.
- DeepSeekplace 2
A record-setting 103.5 mph fastball that was a ball above the zone, so its cWPA was tiny despite the historic velo.
6 AIs put it here - 3
Noah Syndergaard 101.1 mph to Ben Zobrist, 2015 World Series Game 3
The fastest World Series pitch by a starter until Misiorowski. It was a first-inning ball, so the stakes were low. Some early reports said 101.4–101.5 mph.
Included it: Claude, Meta, Grok, Gemini, DeepSeek. Did not include: ChatGPT.In their lists: Claude: 5 · Meta: 5 · Grok: 3 · Gemini: 9 · DeepSeek: 3
What each AI noted 5
- Claudeplace 5
It was the fastest starter pitch in a World Series until Misiorowski's night, and it still holds as the second-fastest by a starter in a World Series game.
Source ↗ - Metaplace 5
101.1 mph ball to Ben Zobrist in 1st inning 2015 – previous fastest by starter in World Series before Misiorowski
- Grokplace 3
Only prior starter 101+ mph pitch in tracking era, a ball that preceded a double in a pivotal game
Source ↗ - Geminiplace 9
Zipped 100.1 mph over Alcides Escobar's head on pitch one to set an aggressive physical tone, sparking the Mets' lone Fall Classic win.
- DeepSeekplace 3
The previous record for the fastest World Series pitch by a starter was a 101.1 mph ball to Ben Zobrist.
5 AIs put it here - 4
Aroldis Chapman's eight-out save, 2016 World Series Game 5
Probably the high-speed outing that mattered most: 24 pitches at 100+ mph in an elimination win. Its top speed (102.8 mph) is a single-source figure.
Included it: Grok, Gemini, DeepSeek. Did not include: Claude, ChatGPT, Meta.In their lists: Grok: 5 · Gemini: 1 · DeepSeek: 5
What each AI noted 3
- Grokplace 5
Multiple 100+ mph pitches in high-leverage relief, including a series-clinching Game 5 outing
Source ↗ - Geminiplace 1
A grueling 102.1 mph fastball stranded the tying run at third base in an elimination game, shifting Chicago's championship probability by +14.2%.
- DeepSeekplace 5
Chapman threw 24 pitches at 100 mph or harder in Game 5, the most in a World Series game before Misiorowski's 2026 outing.
3 AIs put it here - 5
Jacob Misiorowski 103.2 mph to Ben Williamson, 2026 World Series Game 1
Tied Chapman's old record in the third inning of the same game. The result isn't confirmed, and the stakes were early-game.
Included it: Grok, DeepSeek. Did not include: Claude, ChatGPT, Meta, Gemini.In their lists: Grok: 4 · DeepSeek: 4
What each AI noted 2
- Grokplace 4
Tied Chapman's old record mid-game while building a 2-1 lead in the series opener
Source ↗ - DeepSeekplace 4
The third-inning heater matched the second-fastest World Series pitch on record, but the result kept the cWPA near zero.
2 AIs put it here - 6
Aroldis Chapman 103.2 mph, 2016 NLCS Game 1
Matches the old World Series mark, but in the NLCS. Only one source (the Fox list) gives it, with no result or situation.
Included it: Claude. Did not include: ChatGPT, Meta, Grok, Gemini, DeepSeek.In their lists: Claude: 4
What each AI noted 1
- Claudeplace 4
One of the top Statcast-era postseason readings, and Chapman has several of them.
Source ↗
1 AIs put it here - 7
Joel Zumaya 104.8 mph, 2006 ALCS (radar gun, context)
The fastest pre-Statcast postseason reading, but it comes from a stadium radar gun, so it isn't comparable to the Statcast entries above. Single source.
Included it: Meta. Did not include: Claude, ChatGPT, Grok, Gemini, DeepSeek.In their lists: Meta: 7
What each AI noted 1
- Metaplace 7
104.8 mph in 2006 playoffs by Tigers rookie – fastest pre-Statcast postseason pitch, still cited today
Source ↗
1 AIs put it here
02Worth knowing
What the AIs noticed while building the list.
Misiorowski threw 38 pitches at 100+ mph in Game 1, beating Chapman's 24 from 2016. One report counts 37 of 78.
The fastest tracked postseason pitches came outside the World Series: Mason Miller's 104.5 mph in the 2025 Wild Card Series, then a reported 104.8 mph from Misiorowski in the 2026 NLDS.
The same record pitch read 103.4 mph on the stadium board and 103.5 mph on Statcast, which is why readings from different systems aren't mixed here.
No answer could retrieve a verified cWPA value for any of these pitches (Stathead is paywalled), so the list is ordered by speed, and stakes are described in words, not ranked.
03How we counted
In plain words, no formulas.
1The question
Top 10 Fastest Pitches in World Series History, Ranked by Whether They Changed the Series
2Why this topic
Readers see the speed record book and the title-stakes record book side by side, plus a fair note on why an old radar-gun reading and a Statcast reading are not the same measurement.
3Where it applies
Major League Baseball, World Series and League Championship Series pitches tracked at 100 mph or more, 2008–2026, with older radar-gun readings shown for context
4What we looked at
- Release speed, as a percentile within the pool of postseason pitches at 100 mph or more (Statcast)
- Championship win probability added (cWPA) for the play that pitch ended, as a percentile in the same pool
- The pitch's result (ball, strike, whiff, out, hit) and the count and base situation at the time; ties go to the higher cWPA
- Tracking method shown for every entry: Statcast (2008 onward) or an older stadium radar gun, so readings from different systems are not treated as equal
- MLB Statcast (via MLB.com and AP reporting) — Release speed and result of tracked postseason pitches since 2008
- Baseball-Reference Stathead Pivotal Play Finder — Championship win probability added (cWPA) per World Series play. It is paywalled, and no answer retrieved a verified cWPA value for any pitch here
- Stadium radar guns (pre-Statcast) — Older readings, measured at different points of the pitch's flight, shown for context only and not ranked against Statcast
5Who ranked
The leading AIs, each building its own list of ten independently and naming a source for every place: Claude, ChatGPT, Meta, Grok, Gemini, DeepSeek.
6How the places were set
The same entry written differently by different AIs was counted as one. The more AIs put an entry on their list, and the higher they put it, the higher its place. "AI agreement" shows how many of the AIs had it on their own list. Sources are only those the AIs found themselves; nothing was added by hand.
04Each AI's own list
🇺🇸 Claude8 places · 3 notes
The same question, answered by Claude alone. The final list above combines all the AIs.
- 1Jacob Misiorowski's 103.5 mph first pitch, 2026 World Series Game 1
The new World Series record came on the very first pitch, and he threw 38 pitches at 100 mph or more that night, the most in a World Series game in the tracking era, and Milwaukee won 3-2.
Source ↗ - 2Aroldis Chapman's 104.1 mph pitch to Coco Crisp, 2016 World Series Game 2
It is the fastest tracked World Series pitch by MLB.com's count, and the Fox list leaves it out.
Source ↗ - 3Aroldis Chapman's strikeout of Kelby Tomlinson, 2016 NLCS (104.3 mph perceived)
The strikeout pitch was the last of Chapman's night, at a perceived 104.3 mph, which includes extension and so is a different number from raw release speed.
Source ↗ - 4Aroldis Chapman's 103.2 mph pitch, 2016 NLCS Game 1
One of the top Statcast-era postseason readings, and Chapman has several of them.
Source ↗ - 5Noah Syndergaard's 101.1 mph pitch, 2015 World Series Game 3
It was the fastest starter pitch in a World Series until Misiorowski's night, and it still holds as the second-fastest by a starter in a World Series game.
Source ↗ - 6Mason Miller's 104.5 mph called strike three, 2025 NL Wild Card Series Game 2 (context, outside the LCS/World Series poo
The fastest tracked postseason pitch ever was a called strike three to Carson Kelly, in a 3-0 Padres win.
Source ↗ - 7Aroldis Chapman's 103.7 mph pitch, 2017 AL Wild Card Game (context, outside the pool)
The second-fastest entry on Fox's postseason list came from a single-game elimination round.
Source ↗ - 8Jacob Misiorowski's opening pitch, 2026 NLDS Game 1 (context, outside the pool)
His first pitch against the Padres was reported as 104.8 mph, and MLB's own video page titles a different pitch 104.2 mph.
Source ↗
What Claude noticed
The 103.5 mph pitch was the first of the World Series, so it moved the Brewers' title odds almost not at all. This is the speed-versus-consequence split you describe.
Misiorowski threw 38 pitches at 100 mph or more in Game 1, the most in a World Series game in the tracking era.
The fastest tracked postseason pitch is not from a World Series: Mason Miller's 104.5 mph in the 2025 Wild Card Series.
🇺🇸 Meta10 places · 4 notes
The same question, answered by Meta alone. The final list above combines all the AIs.
- 1Aroldis Chapman 103.2 mph groundout – 2016 World Series Game 2
103.2 mph groundout to second by Coco Crisp in 9th inning – second-fastest ever in Series but actually ended the inning
Source ↗ - 2Jacob Misiorowski 103.5 mph ball – 2026 World Series Game 1
103.5 mph on very first pitch of 2026 World Series – fastest ever tracked in Series, but a ball above zone with near-zero cWPA
Source ↗ - 3Aroldis Chapman 104.1 mph heater (radar-gun) – 2016 World Series Game 2
104.1 mph reported by radar gun same at-bat – shows Statcast 103.2 vs stadium gun gap that still fuels debates
Source ↗ - 4Jacob Misiorowski 104.8 mph strike – 2026 NLDS Game 1
104.8 mph called strike to Fernando Tatis Jr. – fastest postseason pitch in Statcast era, not World Series but beat Miller's 104.5
Source ↗ - 5Noah Syndergaard】 101.1 mph ball – 2015 World Series Game 3
101.1 mph ball to Ben Zobrist in 1st inning 2015 – previous fastest by starter in World Series before Misiorowski
- 6Mason Miller 104.5 mph strikeout – 2025 NL Wild Card Game 2
104.5 mph called third strike to Carson Kelly – held postseason record for one year, 9th pitcher ever at 104+
Source ↗ - 7Joel Zumaya 104.8 mph fastball – 2006 ALCS Game
104.8 mph in 2006 playoffs by Tigers rookie – fastest pre-Statcast postseason pitch, still cited today
Source ↗ - 8Nolan Ryan 100.9 mph fastball – August 20 1974
100.9 mph on primitive laser radar in 9th inning 1974 – adjusted to 108.1-108.5 mph at release, Guinness record
Source ↗ - 9Jordan Hicks 105.1 mph – 2018 regular season, 673 pitches 100+ mph
105.1 mph tied Chapman for hardest ever – his 673 pitches at 100+ in 2018 stood until Misiorowski's 1,115 in 2026
- 10Bob Feller 98.6 mph at plate – 1946 motorcycle test
98.6 mph measured as ball crossed plate vs motorcycle – add 9 mph for release, 107.6 mph estimate
Source ↗
What Meta noticed
Misiorowski threw 10 pitches over 101 mph in the first inning of Game 1, 11 of 13 pitches were fastballs averaging 101.9 mph, and 37 of 78 pitches on the night were 100+ mph.
Stadium boards showed 103.4 mph while Statcast logged 103.5 mph – same pitch, two systems, 0.1 mph gap that fuels the Statcast vs gun debate.
Aroldis Chapman still owns the volume record: 329 postseason pitches at 100+ mph since 2008 via Baseball Savant, most ever, before Misiorowski's 154 in his young career.
Only nine postseason pitches have ever been tracked at 104+ mph since 2008, and Misiorowski threw seven of them in 2026 alone.
🇺🇸 Grok10 places · 3 notes
The same question, answered by Grok alone. The final list above combines all the AIs.
- 1Aroldis Chapman 103.2 mph fastball to Coco Crisp, 2016 World Series Game 2
Ninth-inning groundout that helped lock a series-evening win, far higher leverage than a first-pitch ball
Source ↗ - 2Jacob Misiorowski 103.5 mph fastball to Yandy Díaz, 2026 World Series Game 1
Record speed on the opening pitch of the Fall Classic, taken for a ball with zero count leverage
Source ↗ - 3Noah Syndergaard 101.1 mph fastball to Ben Zobrist, 2015 World Series Game 3
Only prior starter 101+ mph pitch in tracking era, a ball that preceded a double in a pivotal game
Source ↗ - 4Jacob Misiorowski 103.2 mph fastball to Ben Williamson, 2026 World Series Game 1
Tied Chapman's old record mid-game while building a 2-1 lead in the series opener
Source ↗ - 5Aroldis Chapman additional 103+ mph pitches, 2016 World Series
Multiple 100+ mph pitches in high-leverage relief, including a series-clinching Game 5 outing
Source ↗ - 6Jacob Misiorowski 38 pitches ≥100 mph, 2026 World Series Game 1
Record volume of triple-digit heat in a single WS game, helping secure a 3-2 win
Source ↗ - 7Tyler Glasnow 100+ mph pitches, 2020 World Series Game 1
Prior high for a starter with six triple-digit pitches in the series opener
Source ↗ - 8Older radar-gun readings pre-2008 (contextual)
Stadium guns occasionally flashed 100+ but lack Statcast consistency and cWPA linkage
Source ↗ - 9Mason Miller 104.5 mph (2025 postseason, non-WS)
Fastest tracked postseason pitch overall, but outside World Series scope
Source ↗ - 10Aroldis Chapman regular-season peaks (105.8 mph)
Absolute velocity leader but regular-season only, zero World Series cWPA
Source ↗
What Grok noticed
Misiorowski's 103.5 mph opening pitch is the first 103+ mph by any starter in World Series history under Statcast; previous starter high was 101.1 mph.
Chapman's 2016 Game 2 103.2 mph pitch produced a groundout in the ninth of a series-tying game, illustrating how leverage often outweighs raw speed.
Misiorowski threw 38 pitches of 100+ mph in Game 1, shattering the prior World Series single-game high of 24 by Chapman.
🇺🇸 Gemini10 places · 1 notes
The same question, answered by Gemini alone. The final list above combines all the AIs.
- 1Aroldis Chapman (2016 Game 5, 8th Inning)
A grueling 102.1 mph fastball stranded the tying run at third base in an elimination game, shifting Chicago's championship probability by +14.2%.
- 2Kelvin Herrera (2014 Game 2, 7th Inning)
Entering with two on and a one-run lead, his 101.4 mph heater silenced the Giants and sparked Kansas City's lockdown bullpen formula.
- 3Nathan Eovaldi (2018 Game 3, 14th Inning)
Threw a 100.8 mph fastball on his 83rd pitch in extra relief, saving Boston from immediate defeat across a marathon 18-inning game.
- 4Neftalí Feliz (2010 Game 3, 9th Inning)
Locked down Texas's first World Series victory in franchise history by firing a 100.3 mph dart to strand the tying run in scoring position.
- 5Brusdar Graterol (2020 Game 6, 7th Inning)
Unleashed a 101.9 mph turbo-sinker that induced an inning-ending groundout, putting Los Angeles six outs away from their first title since 1988.
- 6Rob Dibble (1990 Game 2, 10th Inning)
Gave the 'Nasty Boys' lore its velocity standard with a 101.0 mph gun reading, preserving a tied extra-inning game that broke Oakland's dynasty.
Source ↗ - 7Jacob Misiorowski (2026 Game 1, 1st Inning)
Set the all-time World Series velocity record at 103.5 mph to punch out Yandy Díaz, establishing psychological dominance in a Game 1 duel.
- 8Bryan Abreu (2022 Game 4, 8th Inning)
Fired a 100.4 mph four-seamer to freeze Philadelphia, preserving the eighth inning of MLB's second-ever Fall Classic combined no-hitter.
- 9Noah Syndergaard (2015 Game 3, 1st Inning)
Zipped 100.1 mph over Alcides Escobar's head on pitch one to set an aggressive physical tone, sparking the Mets' lone Fall Classic win.
- 10Aroldis Chapman (2016 Game 2, 9th Inning)
Hit 104.1 mph on the radar gun against Coco Crisp, setting what stood for a decade as the Fall Classic velocity record in a low-stress 5-1 blowout.
What Gemini noticed
Championship Win Probability Added penalizes raw velocity heavily when pitches occur early in a series: an eighth-inning 100.8 mph pitch in an elimination game swings title odds 35 times more than a 103 mph pitch in the first inning of Game 1.
🇨🇳 DeepSeek10 places
The same question, answered by DeepSeek alone. The final list above combines all the AIs.
- 1Aroldis Chapman's 103.2 mph groundout (2016 World Series, Game 2)
The fastest pitch ever to end a World Series plate appearance with an out, and it carried a 1.08% cWPA swing.
- 2Jacob Misiorowski's 103.5 mph first pitch (2026 World Series, Game 1)
A record-setting 103.5 mph fastball that was a ball above the zone, so its cWPA was tiny despite the historic velo.
- 3Noah Syndergaard's 101.1 mph first-inning pitch (2015 World Series, Game 3)
The previous record for the fastest World Series pitch by a starter was a 101.1 mph ball to Ben Zobrist.
- 4Jacob Misiorowski's 103.2 mph pitch to Ben Williamson (2026 World Series, Game 1, third inning)
The third-inning heater matched the second-fastest World Series pitch on record, but the result kept the cWPA near zero.
- 5Aroldis Chapman's 102.8 mph pitch (2016 World Series, Game 5)
Chapman threw 24 pitches at 100 mph or harder in Game 5, the most in a World Series game before Misiorowski's 2026 outing.
- 6Brusdar Graterol's 102 mph pitch (2020 World Series)
One of only 13 pitches to reach 102 mph in World Series play in the pitch-tracking era before 2026.
- 7Jacob Misiorowski's 103.0 mph pitch to Yandy Díaz (2026 World Series, Game 1, fifth inning)
His third pitch of 103 mph or harder extended the record-setting night, but the game situation was still early.
- 8Aroldis Chapman's 102.7 mph pitch (2016 World Series, Game 2)
The second-fastest pitch of Chapman's 2016 World Series run, part of a record 24-pitch 100+ mph game in Game 5.
- 9Craig Kimbrel's 100.5 mph pitch (2018 World Series)
A 100.5 mph fastball from Kimbrel in the 2018 Fall Classic, when he was still averaging over 97 mph in the postseason.
- 10Josh Hader's 100.0 mph pitch (2018 World Series)
Hader's 100.0 mph fastball was his hardest World Series pitch, but it came in a lower-leverage moment than his regular-season dominance.