Warsaw: Gabriela Knutson vs Sofia Costoulas

Platform comparison

Market context

Gabriela Knutson v Sofia Costoulas in Warsaw is a live tennis trading mismatch on the face of it: sportsbooks have Costoulas around 1.45 to 1.56, which implies roughly a 64% to 69% chance before margin, while one analyst-style tipster feed puts Costoulas at 66% and another model-based page was showing about 55% for the same side.[2][1][4][7] That leaves the contract’s current 100% YES crowd price far above both the bookmaker consensus and the broader analytical view, so the market is pricing in either a stale order book, an uncorrected status issue, or a very strong assumption that Knutson is already through.

Comparable cases in lower-tier WTA markets usually track the pre-match moneyline more closely once the market is active, especially when one player has a clear rankings edge and the head-to-head is limited. Tennistemple lists Costoulas ahead on ranking, and its head-to-head page shows Costoulas leading the matchup 1-0, while there is no broader history of repeated meetings to justify an extreme one-sided price on Knutson.[12][13] In practice, a 100% implied probability is only easy to justify after a result is effectively settled; before that, even strong favourite lines still leave upset risk and settlement risk for any contract tied to advancement rather than simple match completion.[2][12]

The main catalysts are straightforward: official match order, any delay or court reassignment, and whether the fixture actually starts and finishes inside the seven-day settlement window. Live score services and sportsbook listings indicate the match was on the Warsaw schedule for 3 August 2026, but if it is postponed, cancelled, or left unfinished without a winner, this contract can still settle 50-50 under the market rules, which is the key operational risk behind a headline 100% price.[7][10][11] Traders should also watch for any late withdrawal or retirement notice, because that can flip a seemingly settled matchup into a resolution question rather than a pure winner call.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Warsaw: Gabriela Knutson vs Sofia Costoulas across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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 PolyGram. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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.

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.