You're keeping score at a game. The shortstop boots a ground ball that should've been the third out. Next batter hits a home run. Two runs score. Does the pitcher's ERA go up by 2.00?
No. Both runs are unearned because the inning should've been over.
This is where earned vs unearned runs gets confusing. The runs count on the scoreboard. They affect who wins. But they don't count against the pitcher's ERA because the defense screwed up.
The Basic Definitions
Earned Run
Any run that scores without the help of a defensive error or passed ball. The pitcher is responsible for this run and it counts toward their ERA.
Unearned Run
Any run that scores because of an error or passed ball. The run still counts in the game, but doesn't hurt the pitcher's ERA.
According to MLB's official definition, an earned run is "any run that scores against a pitcher without the benefit of an error or a passed ball."
The official scorer makes the call. When an error happens, they reconstruct the inning mentally — what would have happened if the error didn't occur? Any run that still would've scored is earned. Runs that only scored because of the error are unearned.
Why This Matters
Earned runs determine a pitcher's ERA. Unearned runs don't.
When you calculate ERA, the formula only uses earned runs:
ERA = (Earned Runs × 9) ÷ Innings Pitched
A pitcher could give up 6 runs in a game, but if 4 of them are unearned, their ERA only goes up based on the 2 earned runs. The other 4 get blamed on the defense.
This makes sense in theory — why should a pitcher's stats suffer when their shortstop kicks the ball? But it gets complicated fast.
The Two Golden Rules
Rule 1: A batter who reaches base on an error can never score an earned run.
Rule 2: Any run that scores after there should be three outs is unearned.
These two rules handle 90% of cases. The other 10% gets tricky.
Example 1: Simple Error, Two Outs
Inning starts:
- Batter A singles
- Batter B strikes out
- Batter C flies out (2 outs)
- Batter D hits a ground ball to shortstop — ERROR, reaches first base
- Batter E hits a home run, scoring D and himself
- Batter F strikes out
Result: 2 runs scored
Why: Batter D should've been the third out. The inning should've ended there. Batter E never should've come to the plate. Both runs scored after what should've been three outs.
Example 2: Error After Legitimate Baserunners
Inning starts:
- Batter A singles
- Batter B walks
- Batter C reaches on an error (shortstop boots it), bases loaded
- Batter D hits a grand slam (4 runs score)
- Next three batters make outs
Result: 4 runs scored
Reconstruction: Without the error on Batter C, the bases would've been loaded with one out after Batters A and B. Batter D's grand slam still happens. But only Batters A and B score (2 earned runs). Batters C and D don't score because C wouldn't be on base.
Why Batter D doesn't score: Even though he hit the home run, his run is unearned because he only came to bat with the bases loaded due to the error. Without the error, it would've been bases loaded with one out, and his homer would've cleared the bases — but C wouldn't have been there.
This is where it gets weird. Batter D did everything right (crushed a homer), but his run doesn't count as earned because the error put an extra runner on base.
Calculate Your ERA
Track earned runs vs total runs and see how they affect your numbers.
Use ERA Calculator →Example 3: Error Erased by Subsequent Play
Inning starts:
- Batter A singles
- Batter B advances A to third on a passed ball
- Batter C walks (A still on third, C on first)
- Batter D singles, A scores
Result: 1 run scored
Why: The passed ball moved A from second to third. But when C walked, A would've advanced to third anyway (force play). The error got erased by the walk. When D singled, A would've scored from third with or without the passed ball.
This is called "erasing the error." If a subsequent play puts runners where they would've been anyway, the error no longer matters.
Passed Balls vs Wild Pitches
Here's a subtle difference that confuses people:
Passed Ball: The catcher should've caught it but didn't. Counted the same as an error for earned run purposes. Runs that score because of a passed ball are unearned.
Wild Pitch: The pitch was so bad the catcher couldn't catch it. This is the pitcher's fault. Runs that score because of a wild pitch ARE earned.
Same outcome (ball gets away), different responsibility. The official scorer decides which one to call.
Example 4: Wild Pitch vs Passed Ball
- Runner on third base
- Pitcher throws a curveball in the dirt 3 feet in front of home plate
- Ball gets past catcher, runner scores
- Runner on third base
- Pitcher throws a low fastball, catchable but tricky
- Catcher mishandles it, ball rolls away, runner scores
The difference comes down to the official scorer's judgment. A pitch in the dirt that no catcher could handle? Wild pitch. A pitch that got away but should've been caught? Passed ball.
Relief Pitchers Make It Complicated
When a relief pitcher comes in, he "inherits" runners already on base. If those runners score, they count against the previous pitcher's ERA, not his.
Example: Inherited Runners
Pitcher A:
- Gives up a single and a walk (runners on first and second, no outs)
- Gets pulled from the game
Pitcher B (reliever):
- First batter hits a 3-run homer
- Gets three outs
Result: 3 runs scored
Pitcher B: 1 earned run (only the batter he faced)
Pitcher B gave up a homer but only gets charged with one run because the other two were already on base when he came in.
The Weirdest Case: Team Unearned, Pitcher Earned
Sometimes a run can be earned for the pitcher but unearned for the team. This happens when a reliever enters after an error.
Pitcher A:
- Two outs
- Batter reaches on an error (should be third out)
- Gets pulled
Pitcher B (reliever):
- Walks the next batter
- Gives up a 2-run homer
Result: 2 runs scored
Pitcher B: 1 EARNED run (he walked that batter fair and square)
Team: 2 UNEARNED runs (inning should've been over after the error)
Pitcher B gets an earned run charged to his personal stats because he put that runner on base with a walk (no error involved). But the team gets both runs marked unearned because the inning should've ended before either pitcher faced another batter.
Yeah, it's confusing.
What Counts as an Error for Earned Run Purposes?
These defensive mistakes turn earned runs into unearned runs:
- Fielding errors (dropped balls, bad throws, missed tags)
- Passed balls
- Catcher's interference
These do NOT affect earned/unearned status:
- Wild pitches (pitcher's fault, runs are earned)
- Balks (pitcher's fault, runs are earned)
- Hit by pitch (pitcher's fault, any runs are earned)
- Stolen bases (runner's skill, runs are earned)
Basically, if it's the pitcher's fault or the runner's skill, runs are earned. If it's a defensive mistake, runs are unearned.
Does It Actually Matter?
From the pitcher's perspective: yes, because ERA is the main stat everyone looks at.
From the team's perspective: not really. An unearned run still puts a number on the scoreboard. You still lose if you give up more unearned runs than you score.
Some people think the earned/unearned distinction is outdated. A pitcher's job is to prevent runs — period. Splitting hairs about which runs are "really" the pitcher's fault misses the point.
But others argue that ERA and similar stats help isolate pitcher performance from team defense. A pitcher with a 3.00 ERA and terrible defense behind him might actually be better than a pitcher with a 2.50 ERA and Gold Glovers at every position.
Quick Reference
Always Unearned:
- Runner reached on an error and later scores
- Run scores after what should be the third out (due to error)
- Run scores because of a passed ball
Always Earned:
- Runner reached via hit, walk, or HBP and scores
- Run scores on a wild pitch
- Run scores on a balk
- Run scores with no errors in the inning
Scorer's Judgment:
- Would the run have scored without the error?
- Did a later play erase the error's impact?
- Which pitcher is responsible?
Final Thoughts
Earned vs unearned runs exists to separate pitching performance from defensive performance. The idea is fair, but the execution gets messy.
Official scorers have to make judgment calls. Reasonable people can disagree on whether that passed ball should've been a wild pitch, or whether that runner would've scored anyway.
For most fans keeping score at a game, here's the simple version: if an error happens and runs score, mentally replay the inning without the error. Runs that still would've scored are earned. Runs that only scored because of the error are unearned.
As a pitcher, you can't control errors. But unearned runs still hurt your team's chances to win, and they often lead to more pitches thrown, which means you tire out faster. Prevent runs — earned or otherwise — and you'll be fine.