Quality start

In baseball, a quality start is a statistic for a starting pitcher defined as a game in which the pitcher completes at least six innings and permits no more than three earned runs.

The quality start was developed by sportswriter John Lowe in 1985 while writing for the Philadelphia Inquirer.ESPN.com terms a loss suffered by a pitcher in a quality start as a tough loss and a win earned by a pitcher in a non-quality start a cheap win.

Nolan Ryan has used the term "High Quality Start" for games where the pitcher goes seven innings or more and allows three earned runs or less.

As of the end of the 2014 Major League Baseball (MLB) season, the highest "quality start" percentage for a given season in the live-ball era (post-1920) was recorded by Greg Maddux, who had 24 of them in 25 games in 1994. Dwight Gooden was 33-for-35 in 1985.

Since 1921, and through the 2014 MLB season, the overall leaders by percentage (min. 100 starts):

An early criticism of the statistic, made by Moss Klein, writing in The Sporting News, is that a pitcher could conceivably meet the minimum requirements for a quality start and record a 4.50 ERA, seen as undesirable at the time. Bill James addressed this in his 1987 Baseball Abstract, saying the hypothetical example (a pitcher going exactly 6 innings and allowing exactly 3 runs) was extremely rare amongst starts recorded as quality starts, and that he doubted any pitchers had an ERA over 3.20 in their quality starts. This was later confirmed through computer analysis of all quality starts recorded from 1984 to 1991, which found that the average ERA in quality starts during that time period was 1.91.

Another criticism against the statistic is that it is not beneficial for pitchers who pitch many innings per start. If a pitcher allows three earned runs in six innings, he gets a quality start with an ERA of 4.50 for that game. But if a pitcher pitches for nine innings and allows four earned runs, he would have a 4.00 ERA, but would not get a quality start. Former pitcher Carl Erskine said "in my day, a quality start was a complete game ... you gave everybody a day's rest."

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