What is a Quality Start in Baseball?

A quality start in baseball refers to a starting pitcher who throws at least six innings and gave up three or fewer runs in their outing. The stat is a good measurement for organizations and fantasy baseball owners to identify which pitchers gave quality performances during their outing against the opponent. However, earning a quality start does not mean you will get the win for a game. Perhaps the game is tied when you leave after the six, or maybe your team hasn’t scored any runs after you give up one run, and you lose the game 1-0. While the non-win or loss looks terrible on the pitcher, the quality start metric helps explain that the pitcher did their job when they were on the mound.

So, where did the phrase “quality start” come from in baseball? How is a quality start different from a complete game? Who are some of the all-time quality start leaders in Major League Baseball? Why are less and less pitchers getting quality starts to Major League Baseball? Is the quality start an over rated metric? Finally, how is a quality start different from ERA?

Here is the complete breakdown to what a quality start is in baseball.

Who Coined the Phrase “Quality Start” in Baseball?

The phrase “quality start” comes from John Lowe, a sportswriter for the Philadelphia Inquirer in 1985. As the years have gone by, organizations and players expand that phrase to explain different scenarios. For example, Nolan Ryan uses the term “High-Quality Start” to represent a pitcher who pitches seven innings and gives up less than three runs. Another phrase you may hear from the radio and TV announcers is a tough-loss, which means a pitcher lost the game even though they got the quality start.

How is a Quality Start Different from a Complete Game?

A quality start differs from a complete game due to the innings pitched, but a person can achieve both stats in theory. Since a quality start needs to be at least six innings and less than four runs, a pitcher could go all nine innings and give up less than four runs too. If a pitcher can go all nine innings and give up less than four runs, they receive a quality start and complete game.

Who is the All-Time Quality Start Leader?

According to Wikipedia as of 2023, Don Sutton leads all MLB pitchers with 483 quality starts. After him, Nolan Ryan is in second place with 481. Check out the full list from Wikipedia to see more of their stats via wins and losses along with their number of quality performances.

Don Sutton (483)
Nolan Ryan (481)
Greg Maddux (480)
Roger Clemens (465)
Tom Seaver (454)
Gaylord Perry (453)
Steve Carlton (447)
Phil Niekro (442)
Tom Glavine (436)
Tommy John (431)

A Change in Pitching in Recent Years

Sabermetrics and mathematicians now run most of the decision-making for Minor League and Major League Baseball organizations. Statistics and projections lead to teams managing the game in a radically new way. Teams today tend to remove pitchers earlier from games for a few reasons.

First, data implies that baseball players who see the same starting pitcher on their third visit yield a higher average and OPS. Second, if the pitcher pitches over 100 pitches in a game, hitters tend to hit better off them. Third, teams look for quality outs instead of long outings during baseball games. The rise in groups using a baseball opener (reliever who starts the game) suggests using your best pitcher no matter what to get an out. Finally, teams don’t want their starting pitchers to get hurt due to the financial investment, so they take them out to prevent injuries.

With these four examples above, you will see fewer quality starts in the game. Fantrax HQ has a visual that shows a downward trend in innings per game pitched and pitches thrown per game. In 2015, you had 5.81 innings pitcher per game, but 2020 saw that number drop down to 4.8. With this trend, it is safe to conclude that the league average of innings pitched will continue declining year over year.

Is the Quality Start Stat Over-Rated Now?

With the visual above from FanTrax HQ illustrating the decline in innings pitched, you may wonder if the quality start stat is overrated. The answer to that question is that statistics help drive a strategy but don’t need to be the above all be all story. Teams can study many stats like strikeouts, walks, WHIP, wins, earned run average, losses, and more to measure how effective that pitcher is for their team.

Take the Tampa Bay Rays as an example of an organization changing the game for pitching. The Rays were one of the first team to introduce the opener strategy, which was odd since every other team had a starting pitcher start a game. Over the years, more groups began opting for a similar approach using an opener. Since the data suggests that winning at-bats early in the game can lead more wins, teams are using the opener often.

Also, it is worth noting that there is debate if the quality start is overrated. For example, if a pitcher consistently went six innings and gave up three runs, they would have an ERA of 4.5, which is high. During the 2022 MLB season, the average ERA for all teams was a 3.96, which means that a quality start pitcher is actually worse than the league average.

How is a Quality Start Different from ERA?

The main difference between a quality start pitcher and ERA is that a quality start needs a pitcher to go six innings and give up three earned runs or less. As long as a pitcher did that and left the game, they will get a quality start. If you had to average out a pitcher over a season giving up three runs over six innings, they would have an ERA of 4.5, which is bad.

ERA, on the other hand, calculates the number of earned runs a pitcher gives up over nine innings of play. ERA is more important than a quality start in some cases, especially for relief pitchers. Relief pitchers are only coming in for an inning or two during a game, so they won’t have the chance to get a quality start. However, their ERA still combines their performance over nine innings, so if they have one inning in relief where they give up three runs, it will negatively impact their ERA more than a pitcher going six innings and giving up three runs.

Conclusion: What is a Quality Start in Baseball?

In summary, a quality start is one of several metrics that teams can use the evaluate how effective a pitcher is. For instance, there are great pitchers on bad teams who don’t earn enough wins. If an owner only looks at a Wins to Loss ratio, they may overlook that pitcher during free agency. However, there might be a team who use statistics to find hidden talent. Maybe a team looks at quality start as the most important metric, so they will favor that during the offseason.

Also, it is worth noting that there are flaws with the quality start metric in baseball. To start, relief pitchers won’t have the chance to get a quality start because they only come in for an inning or two of work. Therefore, if you were comparing pitchers against each other to see who had more quality starts, then the relief pitchers will never be able to record this metric.

Another flaw of the quality start metric is that, in theory, a pitcher who only pitches six innings and gives up three earned runs will be worse in ERA than the league average. Throwing six innings and giving up three runs results in a 4.5 ERA. During the 2022 MLB season, the league average ERA was 3.96, so shooting for a 4.5 ERA is worse than what the league does on average.