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Single-Season Leaders & Records for Win Probability Added (WPA)

Photo of Lefty Grove+ Photo of Dwight Gooden Photo of Lefty Grove+ Photo of Bob Feller+ Photo of Willie Hernandez Photo of Carl Hubbell+ Photo of Dean Chance Photo of John Hiller Photo of Sandy Koufax+ Photo of Steve Carlton+ Photo of Pedro Martinez+ Photo of Greg Maddux+ Photo of Bob Gibson+ Photo of Sandy Koufax+ Photo of Sandy Koufax+ Photo of Doug Corbett Photo of Lefty Grove+ Photo of Bob Gibson+ Photo of Juan Marichal+ Photo of Bill Lee

+ - Indicates Hall of Famer. Bold indicates active player.

Statistic Description: Win Probability Added by Pitcher Given average teams, this is the change in probability A change of +/- 1 would indicate one win added or lost.

Only players who finished in the top 40 for the majors in a season will appear on this list.
Leaders from the current season are only included for rate stats after July 1st.

This statistic is computed from play-by-play data which is only complete from 1974 to the present. From 1930-1973, the data is incomplete, though for most seasons only less than 20 games per season total are missing. Please see our page on data coverage for a full view of the data used to create these lists.

Note that seasons prior to 1876 are not included in single-season marks, but are included in career marks.