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Baseball’s labor fight might get ugly in two months, but for now, we have the joy and chaos that is the postseason. And since the whole purpose of a baseball projection system is to project baseball, the ZiPS game-by-game postseason probabilities are now live. These projections are almost certainly going to see some shifts as team rosters, lineups, and starting pitchers firm up as we get closer to the start of play. And when it comes to starting pitchers, the changes could be significant! Hat tip to the last few playoff stragglers for getting their matchups sorted out relatively early on Sunday so I had time to run the tool.

Just to remind everyone, the ZiPS playoff model is rather different than the normal projections you see on the site during the regular season. From April through September, ZiPS needs to see the forest for the trees, but in a short sprint, we can focus more on the individual trees themselves. We can make educated guesses as to who is starting each game, what the lineups will look like, who is healthy and who isn’t, and so on. The ZiPS game matchup tool has a built-in lineup estimator that projects the line of every pitcher and hitter against every opposing hitter and pitcher, so there is no need to look at a team’s generalized offensive strength. The postseason also comes with the benefit of being able to run the full, more robust model of ZiPS rather than the simpler model used during the regular season, a compromise necessitated by the fact that projecting the entire league takes more than a day.

Is the model perfect? Of course not. All models are wrong, but some are useful. The approach I take has benefits in some very specific situations where a team’s seasonal record isn’t a good predictor of performance. For instance, in 2019, ZiPS saw the Nationals as being a far more dangerous opponent for the Dodgers than the conventional wisdom did by virtue of Washington’s ability to concentrate a very large percentage of the team’s innings in a few excellent pitchers. And yes, I will keep using this example until an even better one comes along!

If a particular game’s starters haven’t been officially confirmed, the pitcher listed is my most educated guess. Projections for the Division Series will populate after the Wild Card round has concluded, with the Championship Series projections coming after the Division Series wraps up, and so on. For the moment, you’ll see those tabs grayed out. In addition to game-by-game projections, you’ll also find series odds, which will update as each series progresses.

Since FanGraphs offers a few different projection tools, here’s a quick summary of the features of the three models — the FanGraphs Game Odds, the FanGraphs Playoff Odds, and the ZiPS Game-by-Game Odds — that are most relevant for the postseason:

Let the chaos commence!