2.91—1.12 for 1968 season.
That 1968 year was a great year for pitchers. They elevated the pitching mound that year. I believe they changed it the next year.
“1.12 for 1968 season.”
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Perhaps the best single season ever for a pitcher in the modern era.
In 1969 they lowered the mound across baseball, largely because of Gibby’s dominance.