Seattle Mariners vs. Cleveland Guardians

Platform comparison

Active sub-markets

Market context

The Cleveland Guardians and Seattle Mariners face off in a Friday night MLB clash at Progressive Field, with the game scheduled for 7:10 PM ET on June 26. The crowd-implied probability of 100% YES for the Mariners is a statistical anomaly, as no professional sport outcome ever carries absolute certainty; even the most favoured team can lose due to a single error, injury, or unpredictable play. This mirrors how Eurovision splits its final score between a 50% jury vote and 50% televote, ensuring no single bloc dictates the winner, or how the Oscars use a preferential ballot for Best Picture to prevent a narrow majority from crowning a film. In both cases, the system acknowledges that absolute consensus is impossible, making the 100% market probability a clear indicator of either a data error or a misunderstanding of voting mechanics rather than a genuine forecast of inevitability.

Traders should monitor the official MLB final statistics for any signs of a postponed game, which would keep the market open until completion, or a cancellation that would resolve it 50-50. Recent news from ESPN confirms the Guardians hold a 42-39 record against the Mariners' 41-41, suggesting a competitive matchup where the 100% probability is unjustified[2]. Watch for announcements regarding player injuries, weather delays, or lineup changes that could shift the odds, as these dependencies are critical in sports prediction markets. The settlement window ending on July 3, 2026, provides ample time for any make-up games, but the primary resolution source remains the official final statistics, which will determine the winner regardless of the initial crowd-implied probability.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote (Polymarket), four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 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.

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.