Yoshinobu Yamamoto: Complete Career Stats, NPB Records, and MLB Profile (Updated May 2026)

By The Yakyu Analyst | Japan Baseball Lab

Table of Contents

1. Introduction
2. Early Life & Background
3. Miyakonojo High School (2014–2016)
4. NPB Career: Orix Buffaloes (2017–2023)
5. MLB Career: Los Angeles Dodgers (2024–present)
6. International Stage
7. Records and Milestones

1. Introduction

When the Los Angeles Dodgers signed Yoshinobu Yamamoto in December 2023 for 12 years and $325 million — the largest pitching contract in professional baseball history — the analytical community split between two camps. The first pointed to his three consecutive NPB Triple Crowns, his 1.82 career ERA, his three Sawamura Awards (Japan’s Cy Young equivalent), and his complete absence from any injured list across seven professional seasons. The second cited the standard NPB translation discount and the general uncertainty around any pitcher crossing the Pacific.

Two and a half seasons into his Dodgers tenure, the data has resolved the debate. Yamamoto is the best starting pitcher in the National League, arguably in baseball. He won World Series MVP in 2025 — including a complete game in Game 2 of the NLCS against Milwaukee and three World Series victories against Toronto — becoming only the second Japanese-born player to win that award (after Hideki Matsui in 2009). Through eight starts in 2026, he owns a 3.60 ERA and 1.00 WHIP while leading the NL in strikeouts per nine.

But to understand Yamamoto, you need to understand where he came from: a small city in Okayama Prefecture, a high school program in Miyazaki that nearly lost him to a social baseball career, and seven NPB seasons that produced the most statistically dominant pitching run in Japanese baseball’s modern era.

For the biomechanical analysis of his pitching mechanics, see our companion piece: [Link: The Engineering of Yamamoto’s Arsenal — A Biomechanical Analysis]

2. Early Life & Background

Yamamoto was born on August 17, 1998 in Bizen City, Okayama Prefecture — a small coastal city of approximately 32,000 people known historically for Bizen ware ceramics. He is the only current MLB player born in Bizen City. His father, Tadanobu Yamamoto, played shortstop for Higashi Okayama Technical High School and was a coach for the local youth baseball team, the Ibe Powerfuls, where Yamamoto spent his early baseball years. His name “Yoshinobu” combines characters from both his parents’ names, and was reportedly given in tribute to Yosuke Takahashi — no, more precisely, his father was a Yomiuri Giants fan and named him after Yoshinobu Takahashi, who debuted for the Giants as a first-round draft pick the same year (1998) Yamamoto was born.

His sister is an English teacher in Japan — a detail that appears in his official MLB.com bio and which Yamamoto has cited as one reason he has made more effort than most Japanese players to communicate directly in English with teammates and media.

Youth Baseball

Yamamoto began organized baseball in first grade (age 6–7) with the Ibe Powerfuls, the same youth team where his future Orix Buffaloes teammate Yuma Tongu also played — a coincidence that became a footnote in both players’ careers. He played as a second baseman and pitcher throughout elementary school, and by middle school was competing in national competitions as both. His middle school years were spent in Bizen City before he made the decision — unusual for Japanese youth players — to travel to Miyazaki Prefecture for high school specifically to attend a baseball-focused program.

The Name and the Number

Jersey number 18 in Japanese baseball is traditionally reserved for the staff ace — a convention dating to Masaichi Kaneda, who wore it for the Kokutetsu Swallows in the 1950s and became one of NPB’s greatest pitchers. Yamamoto wore #18 for the Orix Buffaloes throughout his NPB career, and when he joined the Dodgers, he requested and received the same number — making him one of a small number of Japanese players to maintain the same jersey across both leagues. The number is more than a preference; it carries institutional weight in Japanese pitching culture.

3. Miyakonojo High School (2014–2016)

Yamamoto enrolled at Miyakonojo High School in Miyakonojo City, Miyazaki Prefecture — approximately 700 km from his hometown in Okayama — specifically because the program offered a focused baseball development environment. He entered as an infielder-pitcher but converted to full-time pitcher in the autumn of his first year.

Development and Velocity

His velocity progression at Miyakonojo was rapid: by his second year he was recording fastballs above 150 km/h (93 mph), an unusual benchmark for a high school pitcher. In his third year he was clocked at 151 km/h in a prefectural tournament game — establishing him as a nationally recognized prospect despite never appearing at Koshien, which Miyakonojo did not qualify for in his three years there.

The absence of Koshien experience is analytically significant for two reasons. First, it meant Yamamoto’s high school arm was not subjected to the consecutive-game, high-pitch-count stress that characterizes elite Koshien aces — a factor that may contribute to his subsequent durability record. Second, it meant that national scouts were evaluating him from prefectural tournament footage rather than the Koshien stage, which created an information gap that explains why he was taken in the fourth round rather than the first.

There is a documented footnote to his final high school summer: Yamamoto has revealed in interviews that he pitched his prefectural tournament games in significant elbow pain, telling no one — including his coaches — that he was injured. He stated that had he thrown one more game, he risked serious damage. The injury resolved during his NPB rookie year without requiring surgery. This episode is a case study in the culture of concealment around player health in Japanese high school baseball — the same culture that drives the Koshien arm health problem discussed in our dedicated piece: [Link: Koshien Tournament Format and the Arm Health Crisis]

Draft and Signing

Before the 2016 NPB Draft, Yamamoto had accepted an offer to join a corporate (shakai-jin) baseball team — the standard alternative to professional baseball for players not taken in early draft rounds. He reversed this decision at the last moment before the draft, submitting his professional availability declaration and ultimately being selected by the Orix Buffaloes in the fourth round on October 20, 2016. He signed for a contract bonus of 40 million yen with an annual salary of 5 million yen — modest figures for what would become one of the most valuable pitching contracts in history eight years later.

4. NPB Career: Orix Buffaloes (2017–2023)

Year-by-Year Pitching Statistics

★ Triple Crown pitching seasons (ERA, wins, strikeouts leader). 2020 season: COVID-19 shortened schedule; Yamamoto deployed as reliever. ERA+ for 2021 season: 222 (from NamuWiki compiled data). Sources: Wikipedia, MLB.com official bio, NamuWiki career data.

Reading the Development Curve

2017–2019: Emergence. Yamamoto’s first three seasons established him as one of NPB’s most promising young arms. His 2018 full-season debut (8W, 2.20 ERA, 149 K in 126.2 IP) was exceptional for a 19-year-old, and his 2019 ERA title (1.99, first of four career PL ERA titles) announced him as a genuine ace. His walk rate declined sharply in this period — from 2.6 BB/9 in 2018 to 2.2 in 2019 — reflecting the command development that became his signature.

2020: The Relief Year. The COVID-19 shortened season deployed Yamamoto as a reliever in 60 appearances rather than a starter — an unusual deployment for an ace-level pitcher that was driven by schedule uncertainty and roster management rather than any evaluation of his starting ability. His 2.10 ERA and 0.95 WHIP from the bullpen confirmed his effectiveness in any role.

2021–2023: The Three-Crown Run. Yamamoto’s three consecutive Triple Crowns (ERA, wins, strikeouts) from 2021–2023 are the most directly comparable achievement to elite MLB dominance in NPB history. Only three MLB pitchers have won three consecutive Triple Crowns: Sandy Koufax, Walter Johnson, and Grover Cleveland Alexander. Yamamoto joins that company by the corresponding NPB standard. His 2023 season — 1.21 ERA, the lowest of the three — featured the most efficient pitching of his NPB career: a WHIP of 0.78, a walk rate of 1.3 BB/9, and a no-hitter on September 9 against the SoftBank Hawks in a start attended by numerous MLB front office representatives who had traveled to Japan specifically to evaluate him before the posting period.

The Sawamura Award

The Eiji Sawamura Award is NPB’s highest individual pitching honor, awarded since 1947 to the season’s most outstanding starting pitcher. Selection criteria include a minimum of 10 wins, 200 innings pitched, 150 strikeouts, a winning percentage above .600, and an ERA below 2.50. Yamamoto won it three consecutive times (2021, 2022, 2023) — the second pitcher in NPB history to achieve three consecutive Sawamura Awards after Hideo Nomo (1989–1990 and then later). The 2022 selection committee chair noted that “there were no competitors” in making the award — an unusual public acknowledgment of the gap between Yamamoto and the rest of the league.

Two No-Hitters

Yamamoto threw two no-hitters during his NPB career:

• June 18, 2022 — vs. Saitama Seibu Lions, 2-0. The fourth no-hitter in NPB that calendar year, an unusual concentration that was partly attributed to the league-wide tracking installation improving pitchers’ access to pitch design feedback.
• September 9, 2023 — vs. Fukuoka SoftBank Hawks. Thrown in front of a documented group of MLB scouts and front office personnel who had traveled to Japan to observe him ahead of his anticipated posting. The timing — his final month of NPB eligibility — gave the no-hitter an additional narrative dimension that made it one of the most-covered NPB games in international media history.

5. MLB Career: Los Angeles Dodgers (2024–present)

Yamamoto signed a 12-year, $325 million contract with the Dodgers on December 22, 2023 — surpassing Max Scherzer’s previous record ($210 million) as the largest pitching contract in MLB history. The signing reunited him with Shohei Ohtani, who had signed with the Dodgers two weeks earlier, creating a rotation headlined by two Japanese aces for the first time in MLB history.

MLB Pitching Statistics

*2026 stats as of approximately May 20, 2026. Sources: CBS Sports, ESPN, RotoWire, Baseball Savant. Career ERA of 2.64 per Wikipedia through April 21, 2026. 2025 IP and some figures estimated from multiple sources; verify at Baseball Reference for precision.

2024: Debut Season and Injury

Yamamoto made his MLB debut on March 21, 2024 in Seoul, South Korea — the Dodgers’ Opening Series against the Padres — and was roughed up for five runs in one inning in an inauspicious beginning. He recovered to post excellent performances through mid-June (ERA under 2.50 through 12 starts) before being diagnosed with a right rotator cuff strain that ended his regular season in mid-June. He returned for the postseason, going 2-0 with a sub-2.00 ERA across his playoff starts as the Dodgers won the World Series against the New York Yankees. His full-season ERA of 3.00 in just 90 innings significantly understated his quality-of-performance profile when healthy.

2025: World Series MVP

Yamamoto’s 2025 season was the definitive statement of his MLB ability. His regular season (2.49 ERA, 30 starts, 173.2 IP, 14 HR allowed) was his most complete MLB campaign, earning him his first MLB All-Star selection. The postseason elevated his profile to historic levels:

• NLCS Game 2 vs. Milwaukee Brewers: Complete game (9 innings), 4 baserunners allowed, 7 strikeouts — the first playoff complete game by any pitcher since Madison Bumgarner in the 2014 World Series. The Dodgers won 1-0.
• World Series vs. Toronto Blue Jays: Three wins (Games 1, 4, and 7 in relief), ERA 0.00 across 14.1 postseason innings. He threw the final pitch of the 2025 World Series — a splitter to George Springer that ended a 3-2 Dodgers victory in Game 7 — and was unanimously named World Series MVP. He became the second Japanese-born player to win World Series MVP after Hideki Matsui (2009).

2026: Early Season and Recent Struggles (Through May 20)

Yamamoto opened 2026 as the Dodgers’ Opening Day starter for the second consecutive year — the first Japanese-born pitcher to start consecutive Opening Days — and won, extending a run of Opening Day success. Through his first three starts he posted a 2.10 ERA and 0.82 WHIP (per CBS Sports). His performance has since softened: across his last four starts through approximately May 20 he has allowed at least three runs in each outing, raising his season ERA to 3.60 and drawing analytical attention to a home run rate (8 HR in approximately 50 IP) that exceeds his 2025 regular season pace (14 HR in 173.2 IP).

Baseball Savant’s 2026 profile shows opponents posting an average exit velocity of 89.6 mph and a barrel rate of 9.2% against him — both above his 2025 levels, suggesting some quality-of-contact regression. Whether this is a small-sample fluctuation, a mechanical adjustment period, or a genuine performance shift requires additional data to determine. His strikeout rate (approximately 8.6 K/9) and walk rate (approximately 1.8 BB/9) remain consistent with his career profile, which supports the small-sample interpretation.

6. International Stage

Tokyo Olympics 2020 (2021)

Yamamoto represented Japan at the Tokyo Olympics, appearing in two games (one start). His tournament line: 0-0, 1.59 ERA, 18 strikeouts across approximately 11.1 innings. Japan went 5-0 in the tournament and won the gold medal. Yamamoto was named to the All-Olympic Baseball Team — the tournament’s equivalent of an All-Star selection.

WBC 2023

Yamamoto started Japan’s Pool B game against Australia, pitching four scoreless innings with one hit and eight strikeouts. He did not pitch in the knockout rounds due to workload management protocols — the Dodgers’ interest was already well-known, and Japan’s management was careful with his arm ahead of the posting period. Japan won the WBC championship, defeating the United States 3-2 in the final.

WBC 2023 line: 1 start, 4.0 IP, 0 ER, 1 H, 0 BB, 8 K

WBC 2026

Yamamoto served as one of Japan’s ace starters for WBC 2026 (held in March 2026). Japan did not win the championship — per available reporting, Japan was eliminated in the quarterfinals amid struggles from the pitching staff’s overall management. Yamamoto’s individual performance in the tournament was reported as strong, but Japan’s early exit was a notable result given their 2023 championship.

7. Records and Milestones

Continue exploring:

• [Link: The Engineering of Yamamoto’s Arsenal — A Biomechanical Analysis]
• [Link: The Japanese Splitter — Grip Physics and Why It Breaks Differently]
• [Link: NPB Stadium Science — How Kyocera Dome Shaped Yamamoto’s NPB ERA]
• [Link: The Complete Guide to Japanese Baseball] (Pillar Page)

Stats last updated: approximately May 20, 2026. MLB figures sourced from CBS Sports, ESPN, Wikipedia, Baseball Savant, and RotoWire. NPB figures sourced from Wikipedia, MLB.com official bio, and NamuWiki career data. This page will be updated as the 2026 season progresses. Correspondence: [email protected]