Is a Quality Start a Quality Stat?


Got thinking before last night’s game about the term “quality start”. Sometimes, it feels like it gets tossed around a bit too much and even too loosely when judging a starters performance. Yes, my curiosity got the best of me and I did a little digging to find some possibly surprising info in regards to a quality start.

While determining that of a quality start, you must define the criteria. A quality start is for a starting pitcher to go at least 6 innings and allow no more than 3 earned runs. I’ve read in a couple of places where the term “earned” has not been included in the “definition” of a QS. The majority do include “earned” in defining of the stat, so I’ll roll with it.

So what is my real point here?

Well, part of it is a positive spin and a part is negative. The negative aspect is that a pitcher can receive a QS at the “minimum standards” and have a game ERA of 4.50. To me, a 4.50 ERA is not construed as a quality ERA and that has been one of the biggest arguments against the stat. There’s been calls for an adjustment to the “formula”, but none has yet to truly surface. I tend to lean that direction as well, but here’s where most of my searching turns into a positive.

What I’m about to unveil, on some level, is far from an original thought or idea, but it does bear a fair amount of mention. Taking the somewhat argumentative requirements of a QS, I took the Reds starters who have posted a QS this season and produced this table.

Upon examination of this, a couple of things really jump out at you.

One. Travis Wood and Bronson Arroyo are 1-2 on the staff in QS. Considering they’ve started the most games, you would think that was a given. If you look at their basic stats as far as W-L and ERA (Wood: 4-4, 5.38; Arroyo: 4-6, 5.28), you might think otherwise. That could also lean to the argument that the stat requirements need adjusting.

And it’s no surprise that Edinson Volquez fares very poorly here…but that leads me to the last two columns, the team’s W-L in games where the starters does produce a QS.

Observe those records of each pitcher when they do provide a QS…and then the Reds record overall when a starter has a QS. Next point…

So if we take the Reds record in games where a starter has a QS and compare that to the overall record, we find that a QS, despite the arguments for a change of the criteria, still holds a positive impact on a game provided the staff is able to produce such a start.

The Reds records currently sit at 33-32. By looking at the above table, Cincy has gone 28-10 when a starter achieves a QS. With 65 games under their collective belts (entering today’s game), Reds starters produce a QS 58% of the time. The winning percentage of Reds QS is .737. We constantly hear of the big guys there in Philly, but it deserves a mention here…and a peek.

The Phillies have played in 64 games this season. They also own the best record in the NL (by a half game) with a 38-26 record. You can deduce that those results are somewhat related to the quality starts provided by that staff. Compare the percentages…

% of overall starts = QS: Reds – 58%, Phillies – 66%
W% of QS: Reds – .737, Phillies – .762
Total wins from QS: Reds – 69; Phillies – 81

The numbers directly above reflect if the current percentages maintain themselves throughout the remainder of the regular season. They can obviously fluctuate…and the Reds better hope they do. If you take the Reds winning percentage in games where they don’t get a QS (.185), that will produce another 13 wins for the Redlegs, leaving them with 82 wins on the season. That’s only one more win than the Phillies will get from only QS. The Phillies have a slightly lower winning percentage in non-QS games (.182). That would add 10 more wins for them creating a a total of 91 wins.

So if you really think about this, the quality start is still a bit of a mixed bag, but it does hold its merit. More QS create greater opportunities for more W’s.