Boston Red Sox vs. Seattle Mariners

Platform comparison

Active sub-markets

Market context

Boston beat Seattle 6-2 at T-Mobile Park on 19 June, with Ranger Suárez taking a no-hitter into the seventh inning, so the listed 0% YES price is already pointing at a completed result rather than a live swing factor.[1][5][8] For a binary baseball contract settled on official final statistics, the main read-through is simple: once the game is final, the outcome should map directly to the winning side unless there is an unusual scoring correction or ruling change.[2]

For traders, the relevant comparison is not pre-game team strength but how these contracts behave around delayed settlement. In MLB, a postponed game stays open until it is completed, while a cancelled game with no make-up or a tie resolves 50-50 under the market rules, so the only remaining risk is administrative rather than sporting.[2] That makes the contract’s value more about event finality than momentum, and in practice the on-chain price should track whether the market has recognised the official result and whether the oracle or resolver has ingested it cleanly.

On the crypto side, settlement risk is tied to USDC and the market operator’s resolution process, not to BTC or ETH direction, though broader crypto volatility can still affect collateral demand and secondary-market liquidity. If spot conditions tighten or funding rates and whale flows widen risk appetite across crypto venues, that can influence how quickly mispricings close, but it does not change the underlying MLB settlement mechanics.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically this overview focuses on on-chain pricing: Polymarket's live mid comes from the Polygon conditional-token order book and settles automatically in USDC. The other three venues — Kalshi, Betfair, Manifold — are listed with their platform attributes, because they operate off-chain and a 1:1 comparison of contract mechanics isn't possible.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

FAQ

Where can I trade this market with the lowest fees?

On BTC Prediction, 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.

What does it cost to trade on BTC Prediction?

Zero. BTC Prediction routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

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.