National Bank Open: Tereza Valentova vs Taylor Townsend

Platform comparison

Market context

Polymarket is pricing this contract at **0% YES** today, even though the on-screen settlement is for the winner of the National Bank Open meeting between Tereza Valentova and Taylor Townsend. The market settles through USDC on Polygon via conditional tokens, so the practical question is not just who is favoured, but whether the match is actually completed in a way that produces a clear advance for one player rather than a fallback 50-50 outcome under the event rules.[13]

That low price sits well below most pre-match tennis pricing elsewhere. External models and books have generally made Valentova the modest favourite, with probabilities clustered around the high-50s to low-60s: Dimers gives Valentova about 59.4%, Stats Insider about 59%, Betstamp about 58%, and Kalshi shows a similar split at 63% for Valentova versus 37% for Townsend.[3][6][9][15] For a Polymarket trader, the gap matters because a 0% quote implies the contract is being treated as effectively certain to miss a standard win-or-lose resolution, not merely that Townsend is being backed heavily.[13]

The main catalysts are administrative rather than tactical: whether the match is played on schedule, whether any late postponement pushes it outside the seven-day resolution window, and whether there is a pre-start withdrawal that would force the market into its 50-50 clause instead of a player win.[13] Live-score and odds feeds show the match as part of the Toronto draw, but traders should watch for schedule changes, walkover risk, and any official tournament updates before assuming a normal finish.[2][4][12]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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.