Hits per nine innings
In baseball statistics, hits per nine innings is the average number of hits allowed by a pitcher in a nine inning period; calculated as: / innings pitched. This is a measure of a pitcher's success based on the number of all outs he records.
Compared to a pitcher's batting average against, a pitcher's H/9 benefits from sacrifice bunts, double plays, runners caught stealing, and outfield assist, but it is hurt by some errors. Unlike batting average against, a pitcher's H/9 benefits from outs that are not related to official at bats, as they are recorded on runners after they have reached base.
, Nolan Ryan is the career leader, Sandy Koufax is #2, Clayton Kershaw is #3.