Batting average against

In baseball statistics, batting average against, also known as opponents' batting average, is a statistic that measures a pitcher's ability to prevent hits during official at bats. It can alternatively be described as the league's hitters' combined batting average against the pitcher.

Definition

Batting average against is calculated as:
for which:

H is the number of hits allowed by the pitcher
BF is the number of batters faced
BB is the number of base on balls
HBP is the number of hit batsmen
SH is the number of sacrifice hits
SF is the number of sacrifice flies
CINT is the number of catcher's interference

For example, if a pitcher faced 125 batters and allowed 25 hits, issued 8 walks, hit 1 batsman, allowed 2 sacrifice hits, allowed 3 sacrifice flies, and had 1 instance of catcher's interference, the pitcher's BAA would be calculated as:
Reference site Baseball-Reference.com more simply defines BAA as hits divided by at bats, as "at bats" for a pitcher equates to the above noted denominator :
For example, in 2021, Max Scherzer had the best batting average against in Major League Baseball among qualified pitchers. Scherzer's BAA for the 2021 season was: