Definition of Immaculate Inning

What does the term "immaculate inning" mean in the world of baseball? What is meant by an "immaculate inning"?

An "immaculate inning" occurs when a pitcher strikes out all three batters in a single inning using the minimum number of pitches - nine.

So - no balls, no foul balls with two strikes. Just 1-2-3 strikes, three straight times.

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The "immaculate inning" is probably rarer than you think - in fact, it has only been accomplished a little over 100 times during the history of Major League Baseball (114 as of the time that this entry was written).

The first ever "immaculate inning" was accomplished by John Clarkson of the Boston Beaneaters on June 4th, 1889.

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A number of pitchers have accomplished the task multiple times. Unsurprisingly, this list includes some of the best strikeout artists in the history of the game - Nolan Ryan, Randy Johnson and Sandy Koufax, just to name a few.

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One player - Danny Jackson - has pitched an immaculate inning in a World Series game.

As pitching quality continues to increase in Major League Baseball, so does the number of immaculate innings. There were no immaculate innings pitched in either the 1940s or 1950s, though there were 37 thrown in the 2010s.

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In 2022, two pitchers from the same team - Phil Maton and Luis Garcia of the Houston Astros - threw immaculate innings in the same game.