Miami Marlins vs. Houston Astros

Platform comparison

Market context

The Houston Astros defeated the Miami Marlins 8–5 in their July 20 MLB clash at Daikin Park, with Jeremy Peña’s grand slam and Yordan Alvarez’s two homers snapping Houston’s four-game losing streak [1][4]. On Polymarket, this contract now trades at 0% YES for the Marlins, reflecting the game’s completed outcome rather than a pre-match forecast. The market resolves to “Houston Astros” per the official final statistics, and since the match finished without postponement or cancellation, the 50–50 tie clause is irrelevant [1].

Historically, MLB prediction markets that settle after a game’s completion often show near-zero probability for the losing side once results are confirmed, as conditional tokens on Polygon instantly reflect the final USDC payout distribution [1]. Comparable cases from the 2025 season show similar price collapses to 0% within minutes of the final out, with no meaningful retracement unless a game is officially overturned by the league—a rarity in regular-season play.

Traders should monitor the official MLB final stats page for any post-game adjustments, though no such changes are expected here [1]. The series continues with Games 2 and 3 on July 21 and 22, but this specific contract is already settled in practice. With the settlement window ending in 2026, the 0% price is effectively locked, and no new catalysts will alter the resolution outcome [1][6].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, 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

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.

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.