Cincinnati Open: Sloane Stephens vs Anastasia Potapova

Platform comparison

Market context

The Cincinnati Open meeting between Sloane Stephens and Anastasia Potapova sits in a market where a 100% YES price is only useful if the underlying match has been fully and cleanly settled. The event was listed for 16 August 2026 on the hard courts at the Lindner Family Tennis Center, with match listings and tournament schedules showing it as a second-round women’s singles fixture on Champions’ Court[13][15].

For programme-style read-throughs, the main comparator is that Potapova came in as the higher-ranked player and the head-to-head had already favoured her 1-0, so pre-match models and odds leaned to Potapova rather than Stephens[3][14]. That makes a crowd price of 100% YES on Stephens unusually extreme unless the market is reflecting a completed result, an official advancement update, or a data error; in a bot-driven workflow, that is the sort of position that should be checked against live score feeds before any automated order logic is left to run[1][11].

The practical catalysts are straightforward: official draw updates, match status changes, and any late withdrawal, walkover, suspension or completion notice before the settlement window closes on 23 August. Cincinnati’s published schedule ran second-round play on 16 August and third-round play from 17 August, so a match that was delayed but then finished within the event week would still matter for resolution, whereas a no-contest or unresolved postponement would push the market towards its fallback terms[13]. Recent scoreboard and result pages also indicate the match was completed and recorded as a Stephens win, which is the key item a rules-based monitor would prioritise over pre-match pricing[1][11][9].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Cincinnati Open: Sloane Stephens vs Anastasia Potapova 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 Polymarket Review UK, which mirrors the Polymarket order book at 0% fees.

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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.

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