Cincinnati Open: Arthur Fery vs James Duckworth

Platform comparison

Market context

Arthur Fery against James Duckworth is a Cincinnati Open round-of-64 match that was scheduled for 15 August, with the settlement window extending to 22 August if the result is still unresolved. The current crowd price implies a near-certain Fery advance, but that sits well above the broader market and model range: Kalshi was around 51% for Fery, Polymarket showed Fery at roughly 45-56% depending on the page, Tennis.com projected 58% for Fery, and several bookmaker-style feeds had Fery only a modest favourite, with prices near even money to about 1.80.

That gap matters because this is not a spot where consensus is clean; the read-through from comparable pricing is that the market is treating the contract as far more binary than the underlying tennis outlook. Historical and comparable tennis markets at this stage often cluster close to the shorter-priced side but rarely justify a 100% outcome unless the event is already decided, and here the available public lines still leave meaningful room for an upset or for a contract-specific non-resolution.

The main catalysts are straightforward: whether the match was actually played, whether either player withdrew before start, and whether the tournament order of play shifts again around the 15-16 August round-two window. If the match is postponed beyond seven days from the scheduled date without a winner, or is cancelled or left as a walkover under the market rules, resolution can revert to 50-50, so traders are watching official Cincinnati scheduling updates and any late injury or withdrawal news closely.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Cincinnati Open: Arthur Fery vs James Duckworth across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Kalshi vs Polymarket, which mirrors the Polymarket order book at 0% fees.

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

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Kalshi vs Polymarket. 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 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.