<P> In baseball, a strikeout occurs when a pitcher throws three strikes to a batter during his time at bat . Twenty different pitchers have struck out at least 18 batters in a single nine - inning Major League Baseball (MLB) game as of 2016, the most recent being Max Scherzer of the Washington Nationals on May 11, 2016 . Four players have accomplished the feat more than once in their career; no player has ever struck out more than 20 batters in a nine - inning game . (Tom Cheney struckout 21 in a 16 - inning game .) Charlie Sweeney was the first player to strike out 18 batters in a single game, doing so for the Providence Grays against the Boston Beaneaters on June 7, 1884 . In spite of this, Bob Feller is viewed as the first pitcher to accomplish the feat, since his then - record 18 strikeouts was the first to occur during the 20th century and the live - ball era . </P> <P> Out of the twenty pitchers who have accomplished the feat, fifteen were right - handed and five pitched left - handed . Five of these players have played for only one major league team . Five pitchers--Steve Carlton, Roger Clemens, Randy Johnson, Nolan Ryan and Tom Seaver--are also members of the 3,000 strikeout club . Sweeney has the fewest career strikeouts in the group with 505, while Nolan Ryan, with 5,714, struck out more batters than any other pitcher in major league history . Bill Gullickson and Kerry Wood are the only rookies to have achieved the feat . Tom Seaver concluded his milestone game by striking out the final ten batters he faced, setting a new major league record for most consecutive strikeouts . </P>

Who holds the record for strikeouts in a game