Koji Uehara (上原 浩治, Uehara Kōji, ; born April 3, 1975) is a Japanese professional baseball pitcher who is currently a free agent. He has played in Nippon Professional Baseball (NPB) with the Yomiuri Giants and in Major League Baseball (MLB) for the Baltimore Orioles, Texas Rangers, Boston Red Sox and Chicago Cubs.
A right-handed pitcher, Uehara has a solid MLB career strikeout rate, with 10.73 K/9 and walk rate of 1.36 BB/9 (through the 2016 season). Through the 2016 season, his career 7.91 K/BB is the best in MLB history for a player with at least 100 innings pitched. Uehara won the 2013 ALCS MVP Award, and closed the final game of the 2013 World Series. With his World Series win, Uehara became one of four players in history to have won both a World Series and a World Baseball Classic.
Uehara graduated from the Osaka University of Health and Sport Sciences, and was drafted with the first pick by the Yomiuri Giants in 1998. He had a successful rookie year in 1999, with 15 consecutive wins that broke the all-time rookie record, claimed the Rookie of the Year, Eiji Sawamura Award, and led in wins, ERA, strikeouts and winning percentage.