Seattle Mariners vs. Cleveland Guardians

Platform comparison

Active sub-markets

Market context

The underlying real-world event is the MLB game between the Seattle Mariners and Cleveland Guardians held on Friday, 26 June 2026 at Progressive Field in Cleveland, which concluded with the Mariners winning 3–1. Colt Emerson’s home run and J.P. Crawford’s go-ahead single in the seventh inning secured the victory, with Luis Castillo delivering a strong pitching outing for Seattle [1][5]. This result directly validates the 100% YES crowd-implied probability for the Mariners, as the game has already been completed and the outcome is official.

Historical precedents in MLB prediction markets show that once a game finishes with a decisive win, markets resolving to the winner typically close at 100% with no further volatility, mirroring cases like the 2024 Yankees–Red Sox series where post-game settlements were immediate and final [7]. Comparable regulatory frameworks, including German GlüStV provisions and US CFTC oversight, treat such settled outcomes as non-tradable, reinforcing that no further trading action is possible or permitted. The “no-KYC up to $1,500” accessibility rule, while relevant for pre-game entry, has no bearing here since the event is resolved and the market is closed.

Traders should note that no catalysts remain to watch, as the game has ended and the settlement window is effectively moot; any future announcements regarding the Mariners–Guardians series, such as the June 27 or 28 matchups [4][6], apply to separate markets. Recent coverage confirms the final score and player contributions, leaving no ambiguity for resolution [1][2]. With the settlement deadline of 3 July 2026 now irrelevant due to prior completion, the market’s status is definitively closed.

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'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.

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.