Yuki Matsui

Yuki Matsui (born October 30, 1995, in Yokohama, Japan) is a left-handed relief pitcher, listed at 5-foot-8 and 165 pounds, who joined Major League Baseball as a bullpen arm. His MLB Debut Date was March 20, 2024, and he has worn jersey No. 1 while pitching in a relief role. In the 2024 regular season, Matsui appeared in 64 games and logged 62.2 innings with a 3.734 ERA, 69 strikeouts (9.909 K/9), and a 1.1649 WHIP. He allowed 46 hits and 23 walks, with eight home runs. His batted-ball profile included a 1.22 groundball-to-flyball ratio, and he was credited with nine holds. In 2025, he made 61 relief appearances and threw 63.1 innings, posting a 3.979 ERA with 61 strikeouts (8.668 K/9) and a 1.3579 WHIP, along with one save and three holds. Early 2026 results (through eight appearances) showed 5.0 innings, a 0.60 ERA, 15 strikeouts, and a 0.8667 WHIP, while limiting opponents to a .130 batting average. Pitch tracking in 2026 included a four-seam fastball averaging 91.7 mph and a splitter showing a 58.8% whiff rate. Internationally, Matsui logged an appearance for Japan in the 2023 World Baseball Classic.