Cleveland Guardians vs. Houston Astros

Platform comparison

Active sub-markets

Market context

The Cleveland Guardians are playing the Houston Astros in Houston, and the market’s **21% YES** implies a sizeable underdog chance for Cleveland against a home favourite. That sits below the pre-match moneyline picture seen across US books, where Houston traded around **-140 to -145** and Cleveland around **+119 to +120**, equivalent to an unadjusted Cleveland win probability in the low 40s before vig; the platform spread is therefore a notable gap versus the outright sportsbook read. [1][4][6]

For comparison, prediction venues do not all price the same way: Polymarket-style markets quote a direct probability, while Betfair and Smarkets usually show decimal odds that must be inverted to compare with a percentage, and their fee treatment differs as well, with exchange-style commissions affecting net returns rather than the embedded vig used by sportsbooks. In this matchup, a 21% crowd price looks more conservative than the headline book lines, so traders will usually compare it with the posted starting pitcher, lineup confirmation, and any late weather or postponement risk rather than the opening moneyline alone. [1][4][6]

The main catalysts are lineup news, a late pitching change, or any schedule disruption that could trigger a postponement and keep the market open until the game is completed. The listed first-pitch time is **7:15 pm ET**, and the market rules mean a tie, cancellation with no make-up, or other non-completion resolves 50-50, which matters more on a platform than on a standard moneyline bet. [1][7]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares Cleveland Guardians vs. Houston Astros specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. Live odds come from the Polymarket order book; the other venues' contract details are maintained manually because their APIs aren't directly comparable. Every CTA routes to Polymarket Alternative, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

Where can I trade this market with the lowest fees?

On Polymarket Alternative, 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.

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?

Not under $1,500 of lifetime trading volume. Above that threshold, Polymarket Alternative triggers a quick verification flow that finishes in minutes.