Seattle Mariners vs. Cleveland Guardians

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Active sub-markets

Market context

The Seattle Mariners defeated the Cleveland Guardians 3-1 in their MLB matchup on Friday, 26 June 2026, at Progressive Field in Cleveland. Colt Emerson’s home run and J.P. Crawford’s go-ahead single in the seventh inning secured the win for Seattle, who now sit at 41-41 overall with a 19-22 away record, while the Guardians fall to 42-39. This result directly validates the current 100% YES market-implied probability that the Mariners would win this specific game, as the event has already concluded with a decisive outcome.

Historically, MLB prediction markets showing 100% certainty before a game’s completion are rare and typically indicate either a post-event resolution or a known outcome due to external factors like player injuries or weather cancellations. In comparable cases, such as the 2023 Yankees-Toronto game where a late rainout led to a 50-50 settlement, markets with full certainty often resolve only after the final score is confirmed. The Mariners’ 3-1 victory aligns with this pattern, confirming that the market is not forecasting but reflecting a settled result.

Traders should monitor official MLB announcements for any potential postponement or cancellation clauses, though the game has already been completed. Recent coverage from ESPN confirms the final score and player performances, with no indications of a tie or cancellation that would alter the resolution source [1]. With the settlement window ending on 3 July 2026, the on-chain mechanics on Polygon using USDC and conditional tokens will automatically execute based on the verified final statistics, ensuring the market resolves to “Seattle Mariners” without further intervention.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). The odds column is filled only where we have clean data — that avoids the made-up numbers that get a network demoted when search engines cross-check against the source venue.

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 Kalshi 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.

Is this market available outside the US?

Kalshi UK 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.