Kimbrel joins Pedro Martinez and Clay Buchholz as the only three Red Sox pitchers to strike three batters on nine pitches in a half-inning. Martinez accomplished his feat almost 15 years ago to the date — 18 May 2002 — in the first inning of a game against the Seattle Mariners, while Buchholz did so in the sixth inning of a game against the Baltimore Orioles on 16 August 2012.

The Red Sox have also been victimized by four opposing pitchers in this fashion. The first was Jim Bunning of the Detroit Tigers in the ninth inning of a game on 02 August 1959. Nolan Ryan was the next to accomplish this while pitching for the California Angels on 09 July 1972; he has done the same thing four years earlier with the New York Mets, making him one of four pitchers in MLB history to do so twice and the only one to do so in each league.

Roger Clemens was the next pitcher to fan the side on nine pitches, doing so in the first inning of a game on 18 September 1997 while pitching for the Toronto Blue Jays; it also marked one year to the day that he had struck out 20 batters in a game in one of his last appearances with the Red Sox. The most recent pitcher to accomplish the feat was Justin Masterson, who set down all three batters “by way of the K” on 02 June 2014 while pitching for the Cleveland Indians.

Of note: John Clarkson of the Boston Beaneaters, later to become the Atlanta Braves, is the first pitcher in MLB history to accomplish this feat, striking out Jim Fogarty, Sam Thompson, and Sid Farrar in the third inning of a game against the Philadelphia Quakers, later renamed the Phillies, on 04 June 1889. This makes him the only pitcher to have tossed an immaculate inning in the 19th century.