What is an Error in Baseball
An error in baseball is a misplay by a fielder that allows a batter or baserunner to advance when they should have been put out, and affects earned run averages and batting statistics.
An error in baseball is a misplay by a fielder that the official scorer determines allows a batter or baserunner to advance when they should have been retired with ordinary effort. Errors are official statistical events that affect several key statistics — most notably, runs that score as a result of an error become unearned runs and do not count against the pitcher's ERA.
How an Error Is Scored
The official scorer charges an error when a fielder:
- Drops a fly ball that should have been caught
- Mishandles a ground ball — allows it to go through or between the legs
- Makes a wild throw that allows the batter or runners to advance
- Drops a thrown ball on a play that would have resulted in an out
- Overthrows a base, allowing runners to advance beyond what a good throw would have allowed
Key principle: The error must be a physical misplay — a mental mistake (misjudging positioning, throwing to the wrong base) is typically not scored as an error.
Effect on Statistics
Batting Average
A batter who reaches base on an error is not credited with a hit — the plate appearance is still counted as an at-bat, but the batter gets no hit. This can depress a batter's average in unlucky situations.
ERA (Earned Run Average)
Runs that score as a direct result of an error are unearned runs — they are not counted against the pitcher's ERA. The scorer reconstructs the inning as if the error had not occurred to determine which runs were earned.
Fielding Percentage
Errors directly reduce a player's fielding percentage: $$\text{Fielding %} = \frac{\text{Putouts} + \text{Assists}}{\text{Putouts} + \text{Assists} + \text{Errors}}$$
Types of Errors
- Throwing errors — Wild throws, overthrows, sails, poor trajectory
- Fielding errors — Dropped balls, balls going through the legs
- Dropped third strike — If the catcher drops the third strike, allowing the batter to run (scored as a passed ball or wild pitch depending on the pitch quality)
Modern Perspective: Defensive Metrics
Traditional error counting has significant limitations. Advanced defensive metrics like:
- Ultimate Zone Rating (UZR)
- Outs Above Average (OAA)
- Defensive Runs Saved (DRS)
...capture plays a fielder fails to make that a better fielder would have, which never appear as errors under traditional scoring. A fast shortstop with great range might reach difficult balls and sometimes throw wildly, while a slow shortstop avoids errors by never getting to those balls at all.