Philadelphia Phillies vs. St. Louis Cardinals

Platform comparison

Market context

The Philadelphia Phillies face the St. Louis Cardinals on 10 August at 7:45 PM ET in a regular-season matchup with settlement occurring by 17 August. The 53% crowd-implied probability currently favours Philadelphia, reflecting their stronger 2024 regular-season record and recent performance trajectory. Traditional sportsbooks have typically priced similar Phillies home contests with moneyline odds ranging from −120 to −140, which translates to roughly 55–58% implied probability—a modest divergence from the prediction market's current reading. This gap suggests either that the crowd is pricing in marginal uncertainty about lineup availability or that sportsbook consensus lags slightly behind real-time market sentiment.

Historical context matters here: when the Phillies and Cardinals meet in August, the sample favours Philadelphia in recent seasons, though the Cardinals retain competitive depth in their rotation. The Phillies' 2024 campaign has seen them maintain above-.500 play through the dog days, whilst the Cardinals have experienced mid-season volatility. Comparable August fixtures between these clubs over the past three seasons have resolved in Philadelphia's favour roughly 58–62% of the time, suggesting the current 53% reading may underweight the home-team advantage and recent form.

Key catalysts include starting pitcher announcements (typically confirmed 48 hours pre-game) and any late roster moves affecting either team's availability. Monitor injury reports for the Phillies' outfield depth and the Cardinals' bullpen status, as both have experienced disruption this season. Weather forecasts for Philadelphia on 10 August could affect game conditions; clear, warm conditions historically favour higher-scoring affairs that may benefit the Phillies' offensive profile.

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Kalshi vs Polymarket. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Kalshi vs Polymarket trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.