HR/9 represents the average number of home runs allowed by a pitcher on a nine-inning scale. The statistic is determined by dividing a pitcher's home runs allowed by his total innings pitched and multiplying the result by nine.
HR/9 is a statistic that -- relatively speaking -- is in the control of the pitcher, because defensive positioning plays no factor. Certain pitchers can have success with a high HR/9 rate, as long as they manage to limit their baserunners otherwise -- leading to fewer multi-run home runs. Pitchers with high fly-ball rates are more likely than ground-ball pitchers to have high HR/9 rates. However, some pitchers have mastered the art of allowing fly balls but not many home runs.
In A Call
"homers per nine"