Tatsuya Imai

is a Japanese professional baseball pitcher for the Houston Astros of Major League Baseball (MLB). He has previously played in Nippon Professional Baseball (NPB) for the Saitama Seibu Lions. He made his NPB debut in 2018, and is a three-time NPB All-Star.

Career Amateur career Imai started playing baseball in the first grade of elementary school. While attending Kanuma City Nishi Junior High School, he played for the Kanuma Red Sox, a local club team, and participated in the national baseball tournament. After graduating from junior high school, he enrolled in Sakushin Gakuin High School, where he became the winning pitcher of the 98th National High School Baseball Championship.

Saitama Seibu Lions Imai made his NPB debut in 2018 with the Saitama Seibu Lions. Imai struggled in his early career. His earned run average (ERA) was 4.81 in 2018, 4.32 in 2019, and 6.13 in 2020. He vastly improved in 2021, pitching to a 3.30 ERA. He has posted a sub-3.00 ERA in every full season since then.

On April 18, 2025, Imai and Kaima Taira combined to no-hit the Fukuoka SoftBank Hawks at the Belluna Dome. Imai pitched the first eight innings, with Taira coming in to complete the no-hitter in the ninth inning. On June 17, Imai struck out 17 batters in a game against the Yokohama DeNA BayStars, surpassing a club record previously held by Daisuke Matsuzaka. On June 21, it was announced that Imai, along with first baseman Tyler Nevin, received the May Taiju Life Insurance Monthly MVP.

Houston Astros The Lions posted Imai to Major League Baseball in November 2025, giving two months to sign with a team. On January 2, 2026, Imai signed a three-year contract with the Houston Astros for $54 million. On April 13, Imai was placed on the 10-day injured list for right arm fatigue, retroactive to April 12. On May 25, Imai pitched the first six innings of a combined no-hitter against the Texas Rangers, finished by Steven Okert and Alimber Santa, who was making his MLB debut in the game.

Pitching style Imai is a , right-handed pitcher. With a low three-quarters delivery, he throws a fastball sitting around , which tops out at , an above-average mid-80s slider, and a changeup.