How much does run differential mean to the St Louis Cardinals?

TL;DR

The St. Louis Cardinals have a complex history with run differential, sometimes succeeding despite negative figures. Their current season shows them 7 games over .500 with only a +3 run differential.

Key points

Negative run differential teams can make the postseason.
The 2023 Cardinals are 7 games over .500 with a +3 run differential.
Historical examples show Cardinals teams have overperformed their run differentials.
Run differential is a predictor but not a definitive measure of success.

St. Louis Cardinals

It might come as a surprise, but negative run differential teams sometimes make the postseason. I am not saying that the 2026 Cardinals will finish with a minus in runs, but I’m not saying they are going to make the playoffs, either. Anyhow, I thought I might go all the way back to 1981, let’s take a journey back into time. The 1981 Cardinals outperformed their pythagorean record (what their record should be assuming a normal balance according to run differential) by only three games. That is because of a positive run differential. But, in 1983 they also had a positive run differential and finished 4 games below .500. In 1984, the Cardinals were 6 games above .500 but with a run differential barely above zero. They should’ve been just over .500, according to their pythagorean record. The 1986 Cardinals did the right thing and absolutely nailed their pythagorean record, finishing at 79-82 with a -10 run differential. The 1991 Cardinals should have finished at .500 but were a few games over .500. We could talk about the 2006 Cardinals, but they had a positive run differential and barely finished over their pythagorean record. And yet somehow won the World Series, of course. It doesn’t happen often, but a +19 run team can go all the way. But could a team with a negative run differential have possibly pulled that off? The 2007 Cardinals really paid the piper for that one, finishing with a -104 run differential. That team should’ve been much, much worse though, interestingly enough. So maybe they never paid the piper! Should’ve been 20 games under! Finished 6 games under .500! So strangely enough, that was a team that didn’t give two turds about their run differential. The 2008 Cardinals were another team to absolutely nail their pythagorean record, just as the 1986 Cardinals did. The Cardinals finished 10 games over in 2008, winning 86 games. In 2010, the Cardinals underperformed by quite a bit, +95, & should’ve won 91 games but won 86, ten games over just like the 2008 team. The incredible 2011 team barely overperformed their pythagorean record but was still destined for the postseason. They did have a +70 run differential, however. Then, something happened to the 2012 Cardinals… they had a +100 run differential, but finished 5 games lower than their pythagorean record, making a team that would seemingly be a good postseason team into a third place team. The 2013 Cardinals scored so many runs that them underperforming their pythagorean record didn’t matter. That team should’ve won over 100 games! But 97 wins was enough. It is noted that that team didn’t fare too well in close games. 2014 Cardinals won a lot more than they should’ve. They didn’t overperform their run differential like the 2007 Cardinals did, but they were certainly another outlier finishing at 90 wins with a +11 run differential. The 2018 squad which was lead by both Mike Matheny and Mike Shildt, is the third team that hit their pythagorean record spot on (since 1981). That team actually won 88 games! But somehow finished in 3rd place. And also the Covid shortened 2020 season would make it four. The 2021 Cardinals were another team that really overperformed their pythagorean record, finishing at 90 wins when they had a +34 run differential. Impressive. The 2023 Cardinals are our fifth Cardinals team since 1981 to hit their pythagorean record. This team finished 20 games below .500! Far worse than the 2007 squad. Most fans remember the 2024 team as being a lot better than expected. This is because that team should’ve finished ten games below .500, but Oliver Marmol coaxed a winning record out of a team with a negative run differential. However, an 83 win Cardinals team usually isn’t going to make the postseason. So it’s possible for the Cardinals to have a winning season with a negative run differential, but it would take some opportune circumstances for a team of that caliber to sneak into the postseason. The are however the best example I have come across with success as a negative run differential season performance by the Cardinals. Last year’s team won 4 more games than their pythagorean record, so maybe the Cardinals are pretty good at overperforming their run differential nowadays. They were still under .500, but what about this season? Baseball reference has the Cardinals as a pythagorean record .500 ballclub. I’ve always thought this is about what this team would be, give or take 5 games. Fangraphs has them finishing just below .500 now. Certainly much better than the Las Vegas odds we saw at the beginning of the season. Instead, this season the team is 7 games over .500. But what’s most impressive: they are only +3 runs. And have been a minus for much of the season! There is of course a correlation with run differential, but it’s also much more random than you might think. It’s about as effective as a weather vane. A rather general barometer for the season. But there’s a history to it, and pythagorean records have been around for a while. How meaningful it is for Cardinals fans, I must shrug it off a bit. And there have been teams with a really good run differential in the first half and not so good in the second half, barely over. All sorts of scenarios and situations. Here is a much snarkier article about it that I ran across: It’s hit and miss, but not a bad indicator, really. There are more advanced predictors out there, but it sticks around. It’s fun to look at, simple. But I have to admit, teams that beat their run differential are often more *interesting* than teams that just crush it. How do they do it? It’s often good bullpens and defense, and we have one of those, at least! At least a good closer helps, too. It looks like I will have to go outside the Cardinals world to find a really good negative run differential team. Do they have those?

Q&A

What is the significance of run differential for the St. Louis Cardinals?

Run differential is a measure of a team's performance, indicating the difference between runs scored and allowed, which can predict postseason success.

How did the 2023 St. Louis Cardinals perform despite their run differential?

The 2023 Cardinals finished 7 games over .500 with a +3 run differential, showcasing their ability to outperform expectations.

Which Cardinals teams historically overperformed their run differential?

Historically, teams like the 2007 and 2021 Cardinals overperformed their run differentials, finishing with better records than expected.

Can a team with a negative run differential make the playoffs?

Yes, negative run differential teams, like the 2024 Cardinals, have made the playoffs under certain circumstances, though it's rare.