St. Louis Cardinals vs. Cincinnati Reds

Platform comparison

Active sub-markets

Market context

The St. Louis Cardinals travel to Cincinnati on 24 May for a midweek National League Central matchup against the Reds. First pitch is scheduled for 1:40 PM ET, with settlement contingent on official MLB records by 31 May. The current crowd-implied probability of 48% for a Cardinals victory reflects a near-even assessment, suggesting traders perceive marginal advantage to the home side or uncertainty around roster availability.

Historical context matters here: the Cardinals have won the division matchup in seven of their last ten meetings against Cincinnati, though recent seasonal form carries greater predictive weight than head-to-head records in May. The Reds' home record in early season play has historically been volatile, with performance heavily dependent on starting pitcher quality and bullpen depth. A 48% probability for the visiting Cardinals aligns with typical road-team discounts in baseball, where home-field advantage typically shifts win probability by 3–5 percentage points.

Traders should monitor lineup confirmations through 24 May morning, particularly any late absences from either side's batting order or rotation changes. Cincinnati's starting pitcher assignment and recent form will be critical—the Reds' pitching staff has shown inconsistency in May across recent seasons. St. Louis' injury status, especially among position players, should be tracked via beat reporters covering the Cardinals. Weather conditions at Great American Ball Park, including wind direction and temperature, can materially affect run scoring in day games. Any roster moves or roster-related announcements from either club in the days preceding the match could shift trader sentiment materially.

Methodology

We track St. Louis Cardinals vs. Cincinnati Reds on the five venues with material liquidity for prediction markets. Live odds come from the Polymarket Polygon order book — the only source that ships real-time data under an open licence. For Kalshi, Betfair and Manifold we list platform attributes (fee, KYC, settlement, payment) instead of fabricated odds, because their APIs use non-comparable contract definitions.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

Where can I trade this market with the lowest fees?

On PolyGram, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

PolyGram is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

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 it cost to trade on PolyGram?

Zero. PolyGram routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.