St. Louis Cardinals vs. Cincinnati Reds

Platform comparison

Active sub-markets

Market context

The St. Louis Cardinals host the Cincinnati Reds tonight, with the market sitting close to a coin flip at 47% for a Cardinals win. That is broadly consistent with a game where the teams are near parity rather than one side being strongly favoured. ESPN’s live game page lists the Reds with a slight edge in on-base and slugging, while St. Louis carries the lower ERA, which helps explain why the price is tight rather than decisive. In prediction markets, a mid-40s implied probability usually signals a contest where the likely win margin is being priced as narrow, not a strong team-vs-weak team mismatch.

Recent form adds context, but it cuts both ways. The Reds have produced mixed results against St. Louis over the past year: CBS Sports’ box score archive shows Cincinnati winning 4-1 in June 2025, while a YouTube game recap from later that season describes a 3-0 Cardinals shutout that pushed the Reds further back in the wild-card race. That kind of split is typical of a market that can move quickly on line-up and pitching news. On Polymarket, the market is quoted directly as an implied probability; on Kalshi, Betfair and Smarkets, traders usually translate between contract price, decimal odds and net fees, so the same match-up can look slightly different after commissions and KYC access limits are factored in.

The key catalysts are the confirmed starting pitchers, late line-up changes and any weather or postponement risk, because this market stays open until the game is completed if it is delayed. MLB.com and ESPN are the relevant primary sources for official status and final result. If the game is rained out and not made up, the market resolves 50-50, which is materially different from a normal win-or-loss settlement and is worth checking on books that price outcomes as decimal odds rather than straight implied probability.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares St. Louis Cardinals vs. Cincinnati Reds specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. Live odds come from the Polymarket order book; the other venues' contract details are maintained manually because their APIs aren't directly comparable. Every CTA routes to PolyGram, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Settlement is the biggest difference between the four platforms: Polymarket on-chain in USDC (instant), Kalshi USD via CFTC (T+1), Betfair and Smarkets in local currency via bank withdrawal (T+1 to T+3). PolyGram routes every trade directly into Polymarket's on-chain settlement, which is why payouts land fastest.

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.

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.