Pittsburgh Pirates vs. St. Louis Cardinals

Platform comparison

Active sub-markets

Market context

The Pittsburgh Pirates and St. Louis Cardinals meet again at Busch Stadium after Pittsburgh’s 7-0 win on 20 May, a result that reset the series and highlighted how quickly these markets can move on one game. The current 27% implied chance on the Pirates is broadly consistent with an underdog price, especially with St. Louis having taken the earlier April series in Pittsburgh 4-0 and winning 10-5 on 30 April. Recent head-to-head form still leans Cardinals: StatMuse shows St. Louis are 4-1 in the last five meetings versus Pittsburgh, which is the sort of short-run sample traders tend to use when comparing a Polymarket-style yes/no price with the decimal odds posted on Betfair or Smarkets.

For market context, the main catalysts are the confirmed line-ups, starting pitchers, and any late injury or rest news before the 1:15pm ET first pitch. In MLB, the biggest swings usually come from pitcher changes and weather, not from broader team form, so traders should check whether either club announces a different starter or scratches a key bat on the morning of the game. Platform mechanics also matter: Polymarket and Kalshi quote the same event as a direct probability, while Betfair and Smarkets express it in decimal terms and can differ once commission is included. KYC access is another constraint, since available markets and account opening rules vary by jurisdiction and venue, which can affect where a trader can actually take the opposite side.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We read Pittsburgh Pirates vs. St. Louis Cardinals from four platform perspectives: Polymarket (on-chain CLOB), Kalshi (CFTC-regulated exchange), Betfair Exchange (sports book exchange), Smarkets (peer-to-peer betting exchange). Polymarket's live quote comes directly from the Polygon order book; the other three are listed with their platform attributes — fees, KYC, settlement currency, payment options — because a 1:1 contract comparison without API access would be guesswork.

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.

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 fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, PolyGram triggers a quick verification flow that finishes in minutes.

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.