Roki Sasaki Bio
Roki Sasaki, known across Japan as “the Monster of the Reiwa Era,” is a Japanese professional baseball pitcher for the Los Angeles Dodgers of Major League Baseball (MLB). Born on November 3, 2001, in Rikuzentakata, Iwate, Japan, he first gained fame for a 101 mph fastball in high school and a perfect game in Nippon Professional Baseball (NPB) in 2022. After debuting with the Chiba Lotte Marines in 2021, he joined the Dodgers in 2025 and contributed to their 2025 World Series championship.
Standing 6 feet 2 inches tall and weighing about 187 pounds, Roki Sasaki has built his reputation on overpowering velocity and a devastating splitter. His combination of athletic build and competitive drive has drawn frequent comparisons to fellow Japanese star Shohei Ohtani. Now pitching on the sport’s biggest stage, he continues to add to one of the most talked-about résumés in modern baseball.
Early Life and Background
Roki Sasaki grew up in Rikuzentakata, a coastal city in Iwate Prefecture that was devastated by the 2011 Tōhoku earthquake and tsunami. He was in the third grade when the disaster struck. The tsunami swept away his family home, and his father and grandparents died in the tragedy. Roki Sasaki, his mother, and his two brothers moved into a nursing home during the long recovery period.
The following year, the family relocated to Ōfunato, where Roki Sasaki enrolled in a new school and began playing organized baseball. The structured environment of school baseball helped him channel his energy and grief into the sport, and he quickly rose through local ranks. He graduated from Ōfunato High School, the same program that nurtured his talent through his teenage years.
Path to Professional Baseball
Even as other prestigious high schools recruited him, Roki Sasaki chose to stay at Ōfunato to remain with his teammates. His senior-season fastball, clocked at 101 mph, broke the Japanese high school record previously held by Shohei Ohtani and earned him comparisons to that same superstar. Media outlets quickly labeled him “the Monster of the Reiwa Era,” a nickname that echoed Daisuke Matsuzaka’s earlier title, “the Monster of the Heisei Era.”
Several Major League Baseball organizations hoped Roki Sasaki would pursue a career in the United States, but he declared for the 2019 NPB draft. The Chiba Lotte Marines won the lottery for the right to the first overall selection and chose him. The team signed him to a contract that included a signing bonus of ¥100 million (about US$911,161.73). Concerned about his long-term health, the Marines kept him off the mound for the entire 2020 season before promoting him to the senior roster in 2021.
Roki Sasaki Career
Early Career (2021)
Roki Sasaki made his NPB debut on May 16, 2021, as a member of the Chiba Lotte Marines. In 11 appearances that season, he posted a 3–2 record with a 2.27 earned run average (ERA) and 68 strikeouts across 63 and one-third innings. The Marines rewarded his steady rookie campaign with a spot in the postseason, and he responded in the 2021 Pacific League Climax Series by striking out 10 batters while allowing just one run in six innings against the Tohoku Rakuten Golden Eagles.
Chiba Lotte Marines Breakthrough (2022–2024)
On April 10, 2022, Roki Sasaki pitched a perfect game against the Orix Buffaloes, the 16th in NPB history and the first since 1994. In the same game, he tied the NPB record of 19 strikeouts and set a new league record by striking out 13 consecutive batters, a mark that also surpassed the previous world record. The performance announced him as the most electrifying young pitcher in Japanese baseball.
One week later, on April 17, Roki Sasaki retired 24 more batters to bring his streak of consecutive outs to 52, an NPB record. He finished the 2022 season with a 9–4 record, a 2.02 ERA, and 173 strikeouts in 129 and one-third innings. He followed that with a 7–4 mark and a 1.78 ERA in 2023 and a 10–5 mark with a 2.35 ERA in 2024. On April 28, 2023, he matched Shohei Ohtani’s record for the fastest pitch by a Japanese player in NPB history, throwing at 102.5 mph. On November 8, 2024, the Marines posted him to allow him to pursue an opportunity in Major League Baseball.
Los Angeles Dodgers Era (2025–Present)
On January 22, 2025, Roki Sasaki signed a contract with the Los Angeles Dodgers that included a $6.5 million signing bonus. Because he was under the age of 25 at the time, MLB rules required that the agreement be a minor-league deal. Baseball America and MLB.com both quickly ranked him as the No. 1 prospect in MLB heading into the 2025 season. He made the Dodgers’ opening-day roster and started the second game of the MLB Tokyo Series against the Chicago Cubs on March 19, 2025, allowing one run while striking out Seiya Suzuki for his first MLB strikeout.
Roki Sasaki earned his first major-league win on May 3, 2025, against the Atlanta Braves. A right-shoulder impingement placed him on the 15-day injured list on May 13, and he was transferred to the 60-day injured list on June 20. After a lengthy rehabilitation assignment, he returned on September 24, 2025, in a relief role. He went on to record his first professional save in the opening game of the 2025 National League Division Series against the Philadelphia Phillies, worked three perfect relief innings in the decisive Game 4, and later pitched in the 2025 World Series, which the Dodgers won in seven games for his first career championship.
Driving Style and Strengths
A right-handed pitcher with a three-quarters delivery, Roki Sasaki pairs a four-seam fastball that has averaged between 95 and 100 mph with a signature split-finger fastball known for its sharp vertical drop. After modifying his grip before his MLB debut to a forkball-like hold, he later added arm-side run to a new splitter that he now throws alongside the forkball. In 2025 he swapped a sweeper for a gyro slider, giving him a deeper breaking-ball mix to complement his power repertoire.
Notable Events and Milestones
The April 10, 2022, perfect game against the Orix Buffaloes stands as the defining early milestone of Roki Sasaki’s career, complemented by his 52 consecutive batters retired record and his 102.5 mph tie of Shohei Ohtani’s Japanese velocity record in 2023. In 2025 he added a World Series ring, and on the international stage he earned a gold medal with Japan at the 2023 World Baseball Classic. His spring-debut performance in the Tokyo Series also marked a symbolic homecoming on an MLB mound.
Roki Sasaki Career Wins
Through the end of his NPB tenure in 2024, Roki Sasaki had compiled a 29–15 record with a 2.10 ERA and 505 strikeouts in league play. His first MLB victory came on May 3, 2025, against the Atlanta Braves, and by mid-June 2026 his major-league line stood at a 4–5 record with a 4.66 ERA and 98 strikeouts. Across both leagues, he has collected key playoff victories, including a perfect three-inning relief outing in the decisive Game 4 of the 2025 National League Division Series.
Nippon Professional Baseball Highlights
During his four seasons with the Chiba Lotte Marines, Roki Sasaki was named an NPB All-Star in both 2022 and 2023 and received the Chiba City Special Award “New Era Hometown Impressive Award” in 2022. His 19-strikeout perfect game, 13 consecutive strikeouts, and 52 consecutive batters retired remain marquee accomplishments in Japanese baseball history. He closed his NPB run with a 10–5 record and 129 strikeouts in 2024.
Other Wins and Performances
On the international stage, Roki Sasaki helped Japan capture the 2023 World Baseball Classic championship, finishing the tournament at 1–0 with an 11-strikeout performance across seven and two-thirds innings. His 2025 postseason work for the Dodgers included saves in the first two games of the National League Division Series and appearances in the World Series, capping his first year in the majors with a championship ring.
Roki Sasaki Family
Family Background and Racing Lineage
Roki Sasaki was raised in Rikuzentakata, Iwate Prefecture, alongside his mother and his two brothers. The 2011 Tōhoku earthquake and tsunami claimed the lives of his father and grandparents, a tragedy that reshaped his childhood. He took up baseball seriously after the family resettled in Ōfunato the following year.
Personal Life
Roki Sasaki keeps most of his personal life private and has not publicly confirmed a spouse or children. He measures 6 feet 2 inches tall and weighs about 187 pounds. His given name was inspired by the villain Rouki from the 2001 Super Sentai television series Hyakujuu Sentai Gaoranger.
2025 Season Performance
Roki Sasaki’s first MLB campaign was a study in flashes of brilliance and physical setbacks. He debuted in the Tokyo Series against the Chicago Cubs on March 19, 2025, and earned his first major-league win on May 3 against the Atlanta Braves. A right-shoulder impingement, however, sent him to the injured list in mid-May and limited him to eight starts before his midseason pause.
After returning in late September in a relief role, Roki Sasaki delivered in October, recording saves in the first two games of the National League Division Series against the Philadelphia Phillies and three perfect relief innings in Game 4. He went on to pitch in the 2025 World Series, which the Dodgers captured in seven games for his first career championship. Across his eight starts and two relief appearances, he finished the regular season at 1–1 with a 4.46 ERA, 28 strikeouts, and 22 walks.
Heading into 2026, the Dodgers’ outlook with Roki Sasaki is anchored by his power arsenal and postseason poise rather than by volume. His splitter, forkball, and gyro slider combination gives manager Dave Roberts multiple late-inning options. If he stays healthy, he projects as a frontline starter whose October résumé already includes a perfect multi-inning outing and a championship ring.
