National Bank Open: Adam Walton vs Jenson Brooksby

Platform comparison

Market context

Adam Walton and Jenson Brooksby were still listed for the National Bank Open first round in Montréal, with the match shown as upcoming on Court 9 and broadly priced in Brooksby’s favour. Tennis.com had Brooksby as a 55% projected winner against Walton’s 45%, while other pre-match listings also leaned to Brooksby, with one sportsbook making him a modest favourite and a live-score page showing the contest scheduled for 3 August on outdoor hard courts.[1][5][7][8]

The current 0% YES price is best read as a stale or event-driven line rather than a reflection of on-court form alone. The pair had no prior head-to-head record before this meeting, so there was no direct historical matchup to anchor expectations; in that setting, rankings and market pricing matter more than match-up history, and Brooksby’s higher ranking at the time and stronger pre-match odds help explain why the market would normally skew his way.[2][3][4][9]

For traders, the key catalysts are simple: whether the match has actually started, whether an official result has been posted, and whether any schedule change pushes it beyond the settlement window. The market rules mean a walkover, cancellation, or a delay of more than seven days without a winner would force a 50-50 resolution, so any ATP/organiser update on court allocation, start time, or withdrawal status is more important than pre-match commentary.[5][8][11]

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

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

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.

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.