Beating up on bad baseball teams

Can the Royals early success against struggling teams portend greatness?

Sweeping the White Sox felt pretty good. When a bad team comes to your home park, it is hopefully time to feast, and feast the Royals did. It is the exact opposite of last year in the early season. I remember when Oakland came to town in early May of 2023 and the Royals lost the first two games of the series. That was when I realized how bad of a year it was going to be. The success over the weekend made me go look at who beat up on the bad teams last year and whether the best teams do so at a higher rate than the middle and bottom.

To take a look at this, I had to define who the bad teams were. I ended up with two separate groups of bad. The first was what I deemed the awful group. This is made up of the 2023 A’s, Royals, White Sox, and Rockies. All of them lost more than 100 games. My second grouping I called the bad group, and those were the Angels, Nationals, Cardinals, and Mets. The all lost 75 or fewer. I almost didn’t include the Mets in there since they were at 75, but I decided they had earned the (dis)honor.

Next, I took each teams winning percentage against the awful teams and subtracted their percentage overall. Then again for the bad teams. As you would expect, pretty much everyone has a higher winning percentage against the awful/bad teams except for a few fluky ones because the sample sizes are so small. On average, teams won 14.8% more often against awful teams and 4.9% more often against the bad teams. Those same averages for the 10 best teams in baseball were 15.3% and 5.0%, so pretty much the same. It does not look like the best teams outperform against the bad teams. Everyone does better on average, but the distribution of the improvement looks random.

The correlation between winning percentage and difference in performance against awful and bad teams are -.103 and -.038 respectively. That is low enough to mostly ignore, and both are directionally negative, which means that if anything, the better teams’ win percentages go up less against the bottom teams than the middle and bottom do.

So, it looks like the Royals having success against a bad team is just a normal thing and not so much a sign of more to come. They get to play the Mets, who are struggling at the moment, and then the White Sox again over the next week. Hopefully they can fatten up that record some as the rest of April is going to be stiffer competition.