Polymarket's shallow MLB markets hit by unexplained probability spikes
Polymarket's baseball markets have shown repeated sharp probability swings with minimal liquidity and no disclosed catalysts. On June 6, the Over 10.5 total for Brewers vs. Rockies collapsed from 53.5% to 21% within one hour, with no explanation given. Earlier, the San Francisco Giants' spread (-2.5) saw a notable surge on June 5, while the Seattle Mariners' win probability jumped significantly on June 3 against the Mets. The Milwaukee Brewers also experienced a significant win-probability spike on June 2 versus the Giants, again without volume or causal detail. Separately, a Marlins vs. Mets market showed just $3,500 in liquidity on May 31. None of the sources provided dollar volume, trade counts, or reasoning behind the moves.
Traders have no reliable way to distinguish signal from noise in Polymarket's baseball contracts. Without disclosed volume or market-maker presence, these price swings offer no actionable entry or exit framework.