Before the Red Sox were a thing, the only professional baseball team in Boston was the Beaneaters, who would eventually become the Boston Braves. On June 4, 1889, the Beaneaters took the diamond against the Philadelphia Quakers with righty stud John Clarkson toeing the rubber.
Clarkson led the league in TWELVE pitching categories that season, and the one feat he accomplished that June afternoon would be remembered in the record books for eternity. In the third inning of that contest, Clarkson struck out Jim Fogarty, Sam Thompson, and Sid Farrar on nine pitches, thus making him the first player in baseball history to achieve the immaculate inning.