National Bank Open: Lucrezia Stefanini vs Camila Osorio

Platform comparison

Market context

Polymarket is pricing this USDC contract on Polygon at **0% YES**, which means the market currently assigns no value to a Stefanini advance and is effectively treating Camila Osorio as a near-certainty. For settlement, what matters is the actual match outcome, not the pre-match odds: if the women’s first-round match is played and Osorio advances, the contract resolves to her name; if it is not played, is tied, or drifts more than seven days past the scheduled date without a winner, it resolves 50-50 under the market rules.

The live tennis data lean heavily towards Osorio. She is ranked **WTA 56** to Stefanini’s **144**, and pre-match listings showed Osorio as the stronger favourite on external models as well, with one pre-match estimate around **61%** for Osorio. The historical frame is also one-sided: Osorio has already shown she can compete at this event, reaching the second round in Montreal on debut last year, while Stefanini has not won a main-draw match on tour in 2026 and her lone WTA 1000 main-draw win came against an unranked opponent in Rome in 2024. That combination helps explain why a zero-priced YES can persist even before the first point is played.

For traders, the key catalysts are simple: whether the fixture actually starts, whether there is a last-minute schedule change on Court 1, and whether any weather or draw disruption pushes the match outside the market’s seven-day settlement window. The match was listed for Toronto on outdoor hard courts, with live schedule pages showing an August 2 start time, so a completed result should settle the contract quickly on-chain once the official winner is known. The main dependency is therefore operational rather than speculative: if the opening-round match is completed, conditional token resolution should follow the official outcome; if it is delayed or abandoned, the contract’s fallback rules become relevant.

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Methodology

This page reviews National Bank Open: Lucrezia Stefanini vs Camila Osorio 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 UK, which mirrors the Polymarket order book at 0% fees.

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

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

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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Kalshi 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.