Boston Red Sox vs. Cleveland Guardians

Platform comparison

Active sub-markets

Market context

The Boston Red Sox travel to Cleveland for a day game on 31 May, with the Guardians favoured at the current 47% implied probability for a Red Sox victory. This matchup arrives amid divergent trajectories: Cleveland has maintained consistent competitiveness in the AL Central, whilst Boston's inconsistent early-season form has left them vulnerable in the competitive AL East. Starting pitcher assignments will prove decisive—the Red Sox's rotation depth has been tested by injuries, whilst the Guardians' pitching staff has delivered reliable performances throughout May.

Historical matchups between these franchises show relatively balanced results over recent seasons, though home-field advantage at Progressive Field carries measurable weight in day games. The Red Sox have struggled particularly in afternoon contests this season, posting a notably lower win percentage than evening games, a pattern worth monitoring given the 1:40 PM ET start time. Cleveland's bullpen has been more dependable than Boston's, a factor that compounds if the game remains close into late innings.

Traders should track final roster confirmations released 24 hours before first pitch, particularly any late-inning availability announcements from either side. Recent injury updates to Boston's outfield depth and Cleveland's infield stability could shift the probability materially. Weather conditions at Progressive Field—typically cooler in late May—may suppress offensive output, favouring the Guardians' pitching-focused approach. Line movement in the preceding 48 hours will signal sharp money positioning ahead of settlement on 7 June.

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 Champions League Prediction, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

Where can I trade this market with the lowest fees?

On Champions League 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 does it cost to trade on Champions League Prediction?

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

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, Champions League Prediction triggers a quick verification flow that finishes in 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.