Shinnosuke Ogasawara Bio
Shinnosuke Ogasawara (小笠原 慎之介) is a Japanese professional baseball pitcher who currently plays for the Washington Nationals in Major League Baseball (MLB). He previously spent the bulk of his career in Nippon Professional Baseball (NPB) with the Chunichi Dragons, the team that drafted him out of high school in 2015. A left-handed pitcher known for his curveball, slider, and change-up, Ogasawara earned recognition as an NPB All-Star in 2023 before making the jump to North America in 2025.
Early Life and Background
Shinnosuke Ogasawara was born on October 8, 1997, in Japan, and grew up in Kanagawa Prefecture. His given name, Shinnosuke, was inherited from his grandfather, a family detail he has shared in interviews. While attending Zengyo Junior High School, he played for the Shonan Boys amateur baseball program, the same youth team that produced longtime Dragons teammate Shuhei Takahashi.
During his final year with Shonan Boys, Ogasawara helped the team capture the annual Giants Cup. In the semifinal he struck out nine batters in seven innings while allowing only two runs, and in the final he added three innings with six strikeouts and just one hit allowed. His success in the tournament earned him a place on the Japan U-15 national squad and confirmed his promise as a young pitcher.
Path to Baseball
Ogasawara rose to national fame while attending Tokai University Sagami Senior High School. He became the ace of the squad that won the 2015 Summer Koshien tournament, Japan’s most prestigious high school baseball championship. In the final against Sendai Ikuei Gakuen High School, he delivered 161 pitches and hit a solo home run in the ninth inning to clinch the title. Across six games at Koshien, he threw 26.1 innings with 23 strikeouts and a 3.08 earned run average (ERA).
That same year, Ogasawara represented Japan at the U-18 Baseball World Cup in Osaka, helping the national team reach the final, where they finished as runners-up after losing to the United States. He posted a perfect 0.00 ERA across the tournament, striking out nine Australian batters in six innings and adding two strikeouts in two innings against Cuba in the semifinal. Heading into the 2015 NPB Draft, he was widely regarded as the second-best high school pitching prospect behind Jumpei Takahashi.
Shinnosuke Ogasawara Career
Early Career (2016-2018)
Ogasawara was the contested first-round pick of the 2015 NPB Draft, selected by the Chunichi Dragons after a lottery with the Nippon Ham Fighters. He signed for a ¥100 million bonus plus ¥50 million in incentives and a ¥15 million annual salary, and he was given jersey number 11, previously worn by Dragons ace Kenshin Kawakami. He made his professional debut on May 31, 2016, becoming the first high school rookie to start on opening day of interleague play, and he opened his career with five straight losses.
He finally earned his first victory on September 4, 2016, against the Yomiuri Giants at Tokyo Dome, pitching seven innings with ten strikeouts in a 5-3 win, and added another win against the Yakult Swallows later that month. He finished his rookie year with a 2-6 record, 58 strikeouts, and a 3.36 ERA. After throwing more than 200 pitches in a single fall training session, he suffered cartilage damage in his left elbow that required surgery. He returned in 2017 and started the 2018 season as the Dragons’ opening day pitcher, but a second elbow surgery on August 4, 2018, limited him to 107.1 innings with a 4.11 ERA that year.
Chunichi Dragons Breakthrough (2019-2024)
Over the next several seasons, Ogasawara developed into a reliable member of the Dragons rotation and bullpen. By the end of his NPB career, he had compiled a 46-65 win-loss record, a 3.62 ERA, and 757 strikeouts across his time in the Japanese Central League. His consistency and improved command of his secondary pitches earned him a place on the NPB All-Star roster in 2023, validating the potential scouts had seen in him since high school.
Washington Nationals Era (2025-Present)
On January 24, 2025, Ogasawara signed a two-year, $3.5 million contract with the Washington Nationals. He was optioned to the Triple-A Rochester Red Wings to begin the season, where he posted a 4.80 ERA across three starts. On July 6, 2025, he was promoted to the major leagues for the first time and made his MLB debut that same day, pitching 2⅔ innings in relief. He went on to appear in 23 games with two starts during his rookie MLB campaign, finishing with a 1-1 record, a 6.98 ERA, and 30 strikeouts. On October 29, 2025, he was removed from the 40-man roster and sent outright to Triple-A Rochester.
Driving Style and Strengths
Ogasawara delivers the ball with an overhand arm slot and works with a four-pitch mix. His repertoire features a fastball that sits around 90 mph and tops out near 95 mph, a curveball in the low 60s, a slider, and a change-up that mirrors his fastball delivery. Early in his career he leaned heavily on his fastball-changeup combination, but as he gained experience he learned to land his breaking pitches in the strike zone, raising his strikeout totals.
Notable Events and Milestones
Among his signature moments, Ogasawara owns the record for the worst start to a rookie season in the Japanese Central League, going 0-5 in decisions before his first professional win. His 5-0 start is the worst debut for a high school pitcher in NPB in 55 years. In 2017, he became the first teenage pitcher since Yutaka Enatsu in 1967 to begin his career 2-0 against the Yomiuri Giants, and in 2025 he made a rare appearance as a pitcher batting for himself against Max Fried of the New York Yankees.
Shinnosuke Ogasawara Career Wins
Across his professional career, Ogasawara has accumulated 48 combined wins, 46 in NPB with the Chunichi Dragons and 2 in MLB, split between the Washington Nationals and Triple-A Rochester. His biggest victories have come at the high school, NPB, and MLB levels, beginning with the 2015 Koshien title and most recently highlighted by his MLB debut win in 2025.
NPB Highlights
Over nine seasons with the Chunichi Dragons, Ogasawara posted 46 wins, 757 strikeouts, and a 3.62 ERA. His first NPB win came on September 4, 2016, against the Yomiuri Giants, and his most recent seasons saw him recognized as an NPB All-Star in 2023. He was a steady presence in a Dragons rotation that developed several young arms during his tenure.
Other Wins and Performances
Before turning professional, Ogasawara was the winning pitcher of the 2015 Summer Koshien final and helped Japan take silver at the U-18 Baseball World Cup in Osaka. In 2025, he recorded his first Triple-A win with the Rochester Red Wings and added a victory in his MLB debut season with Washington.
Shinnosuke Ogasawara Family
Family Background and Baseball Lineage
The name Shinnosuke was passed down to him from his grandfather, continuing a family tradition. While specific details about his parents are not publicly confirmed, his upbringing in Kanagawa and his early membership in the Shonan Boys program tied him to a deep regional baseball community.
Personal Life
Ogasawara grew up alongside fellow Chunichi Dragons pitcher Shuhei Takahashi. The two attended the same elementary school, played for the same junior baseball team, the Shonan Boys, and grew up within a ten-minute walk of each other. He has cited Masahiro Yamamoto and Hiroki Kokubo as baseball influences, and he is a longtime fan of pro wrestling, idol group SKE48, and Jurina Matsui.
2025 Season Performance
Ogasawara’s 2025 campaign marked his transition to Major League Baseball. After signing with the Washington Nationals in January, he opened the year in Triple-A Rochester, where he made three starts and posted a 4.80 ERA. His promotion to the majors came on July 6, 2025, and he provided the Nationals with innings out of the bullpen and in spot starts throughout the second half of the season.
Across 23 MLB appearances with two starts, Ogasawara finished with a 1-1 record, a 6.98 ERA, and 30 strikeouts. His most memorable moment came on August 27, 2025, when he batted for himself against Max Fried of the New York Yankees. He was removed from the 40-man roster on October 29, 2025, and sent back to Triple-A Rochester as the organization continues to develop his command on the mound.
Looking ahead, Ogasawara remains under contract with Washington through 2027 at $3.5 million, giving the club time to refine his secondary pitches and bullpen role. With improved fastball command and continued use of his curveball-slider combination, he has a clear path to contributing more innings in the Nationals rotation in 2026 and beyond.