National Bank Open: Ann Li vs Elena Rybakina

Platform comparison

Market context

Ann Li’s match with Elena Rybakina at the National Bank Open is priced as a clear underdog-vs-favourite contest, but not an outright blowout. The crowd-implied **17%** for Li sits below most sportsbook-derived estimates, which cluster around the low- to mid-teens for her and the high 70s to mid-80s for Rybakina; Betus lists Li at +450 and Rybakina at -700, while comparative odds pages show Rybakina around 1.14-1.16 decimal and Li around 5.0-5.98.[3][2][8][11] That leaves the market slightly more sceptical of Li than several books and model pages, but not enough to suggest a major disconnect.

Historical framing points the same way: Rybakina is ranked well above Li and is the name most previews side with, including Tennis Tonic and Dimers, both of which lean heavily towards a straight-sets win for the Kazakh player.[1][6] Comparable pricing elsewhere also supports that read, with Betstamp showing roughly 84% for Rybakina and 16% for Li, close to the current contract’s 17% YES on Li and well short of a true coin-flip.[11] In other words, the contract is behaving like a typical top-10-vs-mid-ranked WTA matchup, where the underdog needs either a big serving day or a flatter-than-expected favourite performance to justify the price.

For traders, the main catalysts are straightforward: confirm the match actually starts, watch for any schedule shift on the Toronto order of play, and check whether both players remain fit after the earlier rounds. This market resolves to 50-50 if the match is not played, tied, or pushed beyond the seven-day window, so a cancellation or extended delay matters as much as the result itself. The key dependency is whether Rybakina, who is the overwhelming consensus favourite across books and model pages, is named in the final session schedule and takes the court on time.[1][2][6][11]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track National Bank Open: Ann Li vs Elena Rybakina 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.

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'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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.