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MLB playoffs1 min read

MLB playoffs 2026: how to actually read win probabilities

October baseball is where casual money floods in and prices get emotional. A guide to reading playoff win probabilities like the market professionals do.

Momus
Published 4 September 2026

October is coming, and with it the season's biggest prediction markets — and its most emotional prices. A short guide to keeping your head when everyone else is pricing with their heart.

Baseball favourites are small favourites

In football a giant can be 80% against a minnow. Baseball doesn't do that: the best team in the sport wins about 60% of its games, and a "heavy" playoff favourite in a single game is maybe 58-62%. That means the underdog wins constantly — not as an upset, but as the base rate. A model's job in October is mostly to tell you how close to a coin flip the matchup truly is.

Short series amplify variance

A five-game series between a 55% and a 45% team ends with the weaker side advancing roughly a third of the time. Nobody choked; the sample was just tiny. When you see a price that implies certainty in a short series, someone is paying for a story.

Where the edges hide

Playoff rotations compress: aces pitch more of the innings, bullpens get stretched across consecutive days, and the starter effect our model prices all season gets bigger, not smaller. That's exactly the terrain where a pitcher-aware model earns its keep — and where casual October money moves prices off the fundamentals. The MLB board runs all postseason, every game, model vs market. Free during the beta.

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Frequently asked questions

Are MLB playoff games harder to predict than regular season games?+

The best team in baseball still loses roughly a third of its games, and short series amplify that randomness — a five-game series is closer to a coin flip than most fans accept. Good models mostly tell you how close to 50/50 a playoff matchup really is.

Why do favourites seem to lose so often in the MLB postseason?+

Because 'favourite' in baseball means 55-60%, not 75%. A 58% favourite loses four times in ten — in a short series that's not an upset, it's the base rate doing its work.

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Every fixture, fully modelled — the correct-score grid, the derived markets, and the written read.

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