National Bank Open: Sho Shimabukuro vs Marin Cilic

Platform comparison

Market context

The match is a first-round ATP National Bank Open meeting between Sho Shimabukuro and Marin Cilic in Montréal, and the market’s 0% YES price is sharply below the rest of the board. Tennis.com’s pre-match projection had Cilic at 63% to win, while Dimers’ model was even more bullish at 56% to 61% for Cilic and listed mainstream moneyline prices around Cilic -140, with Shimabukuro +125[3][18][19]. That leaves prediction-market pricing far more extreme than the sportsbook and model consensus, which is notable because both external references still treated Cilic as the favourite rather than a true coin flip[3][18][19].

Historically, this kind of contract tends to trade away from an obvious misprice once the match is officially underway, but before first serve it can also reflect stale scheduling, thin liquidity, or uncertainty around whether the event will be played as planned. The two players had no previous head-to-head record listed in the available tennis databases, so there is no prior matchup history to anchor the pricing directly[16]. More broadly, a 0% implied probability on one side usually signals the market is pricing in either a near-certain opponent win or a structural issue with the contract mechanics rather than a standard tennis edge, especially when independent previews still assign the underdog a meaningful chance[3][18][19].

The main catalysts are straightforward: official tournament order of play, any last-minute withdrawal, and whether the match is actually completed within the settlement window. Tennis.com listed the fixture as a Round 1 match at the National Bank Open in Montréal, but the available feeds show inconsistent timestamps around 2–3 August, which matters because a postponement beyond seven days would force the contract towards a 50-50 outcome under the rules[3][10][11]. If the match is delayed, suspended, or rescheduled after the stated date, traders will need to watch tournament updates closely because the settlement outcome depends on whether a winner is eventually recorded within the window[3].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track National Bank Open: Sho Shimabukuro vs Marin Cilic 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

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

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.

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.