Opponents batting average

☆ Save On Wikipedia ↗
Sandy Koufax had a .179 batting average against in 1965, the best in Major League Baseball for that season.[1]

In baseball statistics, batting average against (denoted by BAA or AVG), also known as opponents' batting average (denoted by OBA),[a] 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:[2]

B A A = H B F − B B − H B P − S H − S F − C I N T {\displaystyle BAA={\frac {H}{BF-BB-HBP-SH-SF-CINT}}} {\displaystyle BAA={\frac {H}{BF-BB-HBP-SH-SF-CINT}}}

for which:

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:

B A A = 25 125 − 8 − 1 − 2 − 3 − 1 = 25 110 = .227 {\displaystyle BAA={\frac {25}{125-8-1-2-3-1}}={\frac {25}{110}}=.227} {\displaystyle BAA={\frac {25}{125-8-1-2-3-1}}={\frac {25}{110}}=.227}


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 (batters faced less walks, hit by pitch, sacrifice hits, sacrifice flies, and catcher's interference):[3][b]

B A A = H A B {\displaystyle BAA={\frac {H}{AB}}} {\displaystyle BAA={\frac {H}{AB}}}

For example, in 2021, Max Scherzer had the best (lowest) batting average against in Major League Baseball among qualified pitchers.[3][c] Scherzer's BAA for the 2021 season was:[3]

B A A = H A B = 119 644 = .185 {\displaystyle BAA={\frac {H}{AB}}={\frac {119}{644}}=.185} {\displaystyle BAA={\frac {H}{AB}}={\frac {119}{644}}=.185}

See also

Notes

  1. Not to be confused with on-base average (OBA), more commonly known as on-base percentage (OBP).
  2. See section "Player Batting Against", hover over "BA" column header.
  3. See section "Player Batting Against", sort by column "BA".

References