In baseball statistics

Baseball statistics

Statistics play an important role in summarizing baseball performance and evaluating players in the sport.Since the flow of a baseball game has natural breaks to it, and normally players act individually rather than performing in clusters, the sport lends itself to easy record-keeping and statistics...

, hits per nine innings (denoted by H/9) is the average number of hits allowed by a pitcher

Pitcher

In baseball, the pitcher is the player who throwsthe baseball from the pitcher's mound toward the catcher to begin each play, with the goal of retiring a batter, who attempts to either make contact with the pitched ball or draw a walk. In the numbering system used to record defensive plays, the...

 in a nine inning period; calculated as: (hits allowed x 9) / innings pitched

Innings pitched

In baseball, innings pitched are the number of innings a pitcher has completed, measured by the number of batters and baserunners that are put out while the pitcher on the pitching mound in a game. Three outs made is equal to one inning pitched. One out counts as one-third of an inning, and two...

. 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 play

Double play

In baseball, a double play for a team or a fielder is the act of making two outs during the same continuous playing action. In baseball slang, making a double play is referred to as "turning two"....

s, runners caught stealing

Caught stealing

In baseball, a runner is charged, and the fielders involved are credited, with a time caught stealing when the runner attempts to advance or lead off from one base to another without the ball being batted and then is tagged out by a fielder while making the attempt...

, and outfield assist

Assist (baseball)

In baseball, an assist is a defensive statistic, baseball being one of the few sports in which the defensive team controls the ball. An assist is awarded to every defensive player who fields or touches the ball prior to the recording of a putout, even if the contact was unintentional...

s, but it is hurt by some errors

Error (baseball)

In baseball statistics, an error is the act, in the judgment of the official scorer, of a fielder misplaying a ball in a manner that allows a batter or baserunner to reach one or more additional bases, when such an advance would have been prevented given ordinary effort by the fielder.The term ...

. 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.