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Baseball Trivia (General)/ERA rules in mlb


QUESTION: A relief pitcher comes in at top of inning. he walks two, gives up two hits, and three runs come in.  He is taken out and the next pitcher gets them 1,2,3.   What is the ERA of the first reliever?  Did he pitch 0 innings?  

ANSWER: Craig,

 Right, he gets credit for no innings pitched. Since the formula for ERA is
(Earned runs/innings pitched) x 9, his ERA for this outing is mathematically: 0.00. But in actuality, his pitcher does not have the lowest ERA, he has the highest. So his ERA would be represented as infinity.

---------- FOLLOW-UP ----------

QUESTION: To follow up then, this outing has no impact
in his season going forward?  how is infinity
used statisicly?  Is the symbol used in the box
score?  thanks!!


The outing does affect his ERA for the season and his career because that earned run is still going to be charged to him in his totals. gives the pitcher's ERA as "inf"; printed sources I've checked use the infinity sign to represent the ERA. So in other words, if this outing was the guy's entire major league career, he's in select company. Only a baker's dozen guys in all of modern major league history have a career ERA of infinity. See the little chart below.  

Baseball Trivia (General)

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Tom Schott


I will deal with the major leagues only from 19th century to present. I`m good on baseball history, records, statistics, ballparks. I don't do off-the-field stuff. Please if you already know the answer to the question, please don't ask it. I don't want to play "stump the expert."


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