Seattle Mariners vs. New York Yankees

Platform comparison

Market context

The Seattle Mariners travel to face the New York Yankees on 13 August at 1:35PM ET in a regular-season matchup with significant playoff implications for both franchises. The 42% implied probability for a Mariners victory sits notably below the typical moneyline odds offered by major sportsbooks, where the Yankees generally trade between −145 and −155, translating to roughly 59–61% implied probability. This 17–19 percentage-point gap between prediction-market consensus and conventional sportsbook pricing suggests either that prediction-market participants are pricing in factors beyond standard bookmaker models, or that traditional sports betting markets are overvaluing the home-field advantage and recent Yankees form.

Historical precedent indicates that mid-August matchups between these franchises often hinge on roster depth and injury status rather than season-long records. The Mariners have won 11 of their last 18 meetings with New York dating back to 2022, despite the Yankees' superior regular-season win rate over the same period. This pattern reflects the volatility of individual games and the reduced predictive power of aggregate statistics in single-game markets.

Traders should monitor roster announcements through 12 August, particularly any late-breaking injuries to starting pitchers or key position players. The Yankees' recent performance against left-handed starters and the Mariners' bullpen availability in the preceding days represent material catalysts. Weather forecasts for the Bronx on 13 August may also influence run-scoring expectations, particularly given the stadium's dimensions and typical August humidity patterns.

Methodology

This page reviews Seattle Mariners vs. New York Yankees across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Best Prediction Markets, which mirrors the Polymarket order book at 0% fees.

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

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.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

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?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Best Prediction Markets trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.