Bases on balls per nine innings pitched
baseball statistic
In baseball statistics, bases on balls per nine innings pitched (BB/9IP or BB/9) or walks per nine innings (denoted by W/9) is the average number of bases on balls, (or walks) given up by a pitcher per nine innings pitched. It is determined by multiplying the number of bases on balls allowed by nine, and dividing by the number of innings pitched. It is a measure of the bases on balls ability of a pitcher.
Leaders
All but one of the top 25 single-season leaders in BB/9IP through 2018 pitched in the period of 1876–84. George Zettlein was the all-time single-season leader (0.2308 in 1876), followed by Cherokee Fisher (0.2355 in 1876) and George Bradley (0.2755 in 1880). The highest single-season modern day baseball performance was by Carlos Silva (0.4301 in 2005).
The all-time career leaders in BB/9IP through 2022 were Candy Cummings (0.4731), Tommy Bond (0.4787), and Al Spalding (0.5114), all of whom played in the 1870s and 1880s.
The active career leaders in BB/9IP through 2022 were Corey Kluber (1.9683), Michael Pineda (1.9719), and Hyun Jin Ryu (1.9914).
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This entry incorporates text from “Bases on balls per nine innings pitched” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.