National Bank Open: Ann Li vs Elena Rybakina

Platform comparison

Market context

Ann Li’s third-round meeting with Elena Rybakina at the National Bank Open is priced as a heavy Rybakina spot across the board, but the market picture is more extreme on the prediction contract than in sportsbook markets. Sportsbooks are generally showing Rybakina around **1.14-1.16** and Li around **4.75-5.98**, which translates to an implied Rybakina win probability in the mid-to-high 80s before margin; by contrast, the contract’s **0% YES** crowd price implies no meaningful participation on Li advancing, despite the underlying tennis markets still leaving Li a small, non-zero upset chance.[1][3][6][10][12][14]

That gap is easiest to read against the matchup context: Rybakina is ranked **No. 2** and Li **No. 31**, and preview models from tennis-specific outlets also lean decisively towards Rybakina, with one calling her the pick to win in two sets and others framing the match as a straightforward favourite spot.[2][5][9][13] In practical terms, the current contract price looks less like a balanced opinion and more like a thinly traded, binary expression of a consensus that Rybakina is very likely to advance, which is consistent with the strong favourite lines seen at multiple books.[3][10][14]

For traders, the main catalysts are schedule and completion risk rather than matchup analysis. The listed start times are clustered around Friday afternoon local time in Toronto, and the market only settles at 50-50 if the match is not played, tied, or delayed beyond seven days without a winner, so any weather interruption, court-order change, or retirement scenario matters more here than in a normal moneyline bet.[5][6][10][11] If the match begins but is not completed, the advancing player still decides the market, so live retirement news or official tournament updates would be the key dependency to watch.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Best Prediction Markets, which mirrors the Polymarket order book directly.

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 Best Prediction Markets. 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.

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.

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.