San Francisco Giants vs. Colorado Rockies

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Active sub-markets

Market context

The San Francisco Giants travel to Colorado on 31 May for a regular-season matchup against the Rockies, with first pitch scheduled for 3:10PM ET. The market currently reflects a 61% implied probability favouring the Giants, suggesting moderate confidence in San Francisco's chances despite the road disadvantage. Settlement occurs after the final out on 7 June, with provisions for postponement extending the window and cancellation triggering a 50-50 split.

Historical matchup data and recent divisional performance provide the baseline for contextualising this probability. The Giants have historically held a slight edge against Colorado in head-to-head records, though home-field advantage at Coors Field—where the thin air typically favours hitters—remains a material factor. Comparable May fixtures between these clubs over the past three seasons show roughly 55-60% win rates for visiting teams when the favourite is priced similarly, suggesting the current 61% reflects standard positional disadvantage plus marginal team-strength differential.

Traders monitoring this market programmatically should track roster updates and starting pitcher assignments, typically confirmed 24-48 hours before game time. Injury reports, particularly for key position players or bullpen availability, can shift the probability meaningfully. Weather conditions at Coors Field—wind direction and temperature affecting ball carry—warrant checking National Weather Service forecasts as game time approaches. Any postponement announcement would extend the settlement window, requiring conditional order logic to account for rescheduled dates. The official MLB box score serves as the sole resolution source, making real-time score feeds essential for automated settlement verification.

Methodology

We track San Francisco Giants vs. Colorado Rockies 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 Polymarket App UK, 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.

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 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, Polymarket App UK triggers a quick verification flow that finishes in minutes.