Seattle Mariners vs. Cleveland Guardians

Platform comparison

Market context

The Seattle Mariners and Cleveland Guardians are locked in a decisive MLB matchup at Progressive Field on 28 June, with the game scheduled to begin at 1:40PM ET. This contest serves as the series finale, following a tight 4-3 Guardians victory in the previous night’s opener where Chase DeLauter rejoined the lineup after recovering from a rib injury[1]. The current crowd-implied probability of 0% for a Mariners win reflects a stark market conviction that the Guardians, bolstered by home-field advantage and recent momentum, will secure the victory in what is expected to be a pitcher’s duel between Cleveland’s Williams and Seattle’s starter[2][7].

Historically, similar 0% implied probabilities in MLB series finales have preceded decisive home wins when the visiting team suffered a key injury or fatigue, as seen when DeLauter’s return shifted the Guardians’ offensive depth just before this game[1]. Programmatic traders often treat such extreme probabilities as conditional order triggers, deploying bots to copy-trade the dominant side once volume spikes above $150K, as occurred in this market with $158K in moneyline volume[5]. The catalysts to monitor include the final pitching confirmation for both teams, any late-injury updates, and the weather forecast for Progressive Field, which could influence the pitcher’s duel outcome[7]. Recent analysis from the Free Press highlights the Guardians’ -115 moneyline as a strong home bet, reinforcing the market’s directional bias[7].

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 Polymarket Bot UK, 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

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 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 Polymarket Bot UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.