Who has the lowest era in mlb history?
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Who has the lowest era in MLB history for a career?
Ed Walsh
The lowest single-season ERA in league history was posted by Tim Keefe, whose 0.86 ERA in 105 innings pitched for the National League's Troy Trojans in 1880 led his closest competitor by .52 runs. In the American League, Dutch Leonard's 0.96 ERA is a single-season record. Keefe and Leonard are the only two pitchers ever to allow less than one run per nine innings pitched in a single season. The widest margin of victory for an ERA champion is 1.96 runs, achieved when Martínez' 1.74 ERA led Clemens' 3.70 in the American League during the 2000 season. The largest margin of victory in the National League is 1.26 runs—Dazzy Vance's 2.61 ERA over Carl Hubbell's 3.87 in 1930. The smallest margin of victory for an ERA champion is .009 runs. Although the statistic is traditionally recorded to two decimal places by most the 1988 American League title was decided by a margin of less than one hundredth of a run when Allan Anderson's ERA of 2.446 (55 earned runs in  innings) bested Teddy Higuera's 2.455 mark (62 earned runs in  innings). Other contests decided by one hundredth or less include Luis Tiant's 1.91 ERA ahead of Gaylord Perry's 1.92 in 1972 and Mark Fidrych (2.34) over Vida Blue (2.35) in 1976.
Who has the lowest ERA in MLB history for a single season?
Tim Keefe
List of Major League Baseball annual ERA leaders
List of Major League Baseball annual ERA leaders
https://en.wikipedia.org/wiki/List%20of%20Major%20League%20Baseball%20annual%20ERA%20leaders
In baseball, earned run average (ERA) is a statistic used to evaluate pitchers, calculated as the mean of earned runs given up by a pitcher per nine innings pitched.
List of Major League Baseball annual ERA leaders
Major League Baseball recognizes the player in each league[b] with the lowest earned run average each season.
List of Major League Baseball annual ERA leaders
Walsh made his major league debut in 1904 with the Chicago White Sox and pitched his first full season in 1906, going 17–13 with a 1.88 ERA and 171 strikeouts.
Ed Walsh MLB career
He attempted a comeback with the Boston Braves in 1917, but was let go, ending his major league career.
Ed Walsh MLB career
In baseball, earned run average (ERA) is a statistic used to evaluate pitchers, calculated as the mean of earned runs given up by a pitcher per nine innings pitched. Major League Baseball recognizes the player in each league with the lowest earned run average each season. Tim Keefe of the National's League Troy Trojans has the lowest ERA in MLB history for a single season. Ed Walsh, who pitched for the Chicago White Sox and Boston Braves, has the lowest ERA in MLB for a career.