Major League Baseball will implement significant changes in its baseball schedules for the upcoming season in an attempt to create more balanced schedules among its 30 teams. It raises the question of what effect the changes will that have on determining playoff teams.

It’s been long argued that division-leading teams who play in relatively weak divisions have an advantage when determining postseason teams and wild card berths. With teams playing each division opponent 19 times per season, a team’s overall winning percentage can be skewed from mounting up a large number of wins against much weaker divisional teams. For example, 54 (48.6%) of the Los Angeles Dodgers’ wins in 2022 came against its four division opponents. They lost only 22 of their games against the same opponents. The Houston Astros were 51-25 against their AL West Division opponents while the Mets were 50-26 against NL East opposition.

Another factor that has frequently contributed to unbalanced results is teams don’t play against all the other league’s teams in interleague play. Drawing the other league’s weaker teams can boost winning percentages inequitably. Again, using the Dodgers as an example, they were 15-5 against six American League opponents, only one of which was a playoff team (Cleveland). The Chicago Cubs were 3-10 against four tough AL East Division opponents, three of which made the playoffs (New York, Toronto, and Tampa Bay) and a surprisingly good Baltimore team.

Here's a recap of the changes being implemented this season:

** Divisional games will decrease from 76 to 52 (from 19 against each team to 13).

** Other intra-league teams will decrease from 66 to 64.

** Inter-league teams will increase from 20 to 46 (each team will play a four-game home-and-home series against a geographic interleague rival, in addition to one three-game series against the other 14 teams in the other league.)

** All 30 teams will play each other at least one series.

To summarize, less emphasis will be put on results against division opponents and more on interleague opponents.

There’s no way to accurately predict how these changes will impact teams’ records and their potential to claim postseason berths in 2023.

However, I did an analysis in which I used the actual winning percentages of each team’s 2022 results for division play, other league play, and interleague play, and applied the percentages to the new breakdown of games.

The results were mixed. 1) Although there were some minor changes in wins, the same American League teams that actually made the playoffs in 2022, came out the same in the analysis. 2) In the National League, the Brewers replaced the Cardinals for first place in the NL Central. 3) The Mets dropped six wins, thus were not tied with the Braves for first place in the NL East. 4) The Padres and Phillies ended in a tie with same number of wins, but due to head-to-head competition in 2022, the Phillies filled the wild card berth, while the Padres lost their berth.

Of course, my analysis is a retrospective “paper” exercise for the 2022 season. But it demonstrates it is possible for the proposed balanced schedule to have an impact on which teams get playoff spots.

Below are the results of my analysis. The Blue cells represent teams that received wild card berths. Green Cells represent playoff teams with byes in first round.