Granby: Justin Boulais vs Zhizhen Zhang

Platform comparison

Market context

The Granby tournament will host a first-round match between Canadian Justin Boulais and Chinese player Zhizhen Zhang on 13 July 2026. Polymarket currently prices this contract at 100% YES, meaning traders are pricing in Boulais's advancement with absolute certainty. This extreme probability reflects either overwhelming confidence in Boulais's superiority or insufficient liquidity to move the market from its initial seeding. The settlement window extends to 20 July, allowing a week-long buffer for scheduling delays before the market resolves to a 50-50 split.

Historical precedent suggests such lopsided pricing in early-round tennis matches often reflects ranking disparities rather than genuine match certainty. When ATP or ITF tournaments pit significantly higher-ranked players against lower-ranked opponents, conditional token markets frequently price the favourite at 95%+ even when upsets occur at measurable rates. Boulais's career ranking and recent form relative to Zhang's trajectory would determine whether this 100% pricing represents rational expectation or market inefficiency. The Granby event, typically held in Quebec, draws a regional player pool where seeding accuracy varies considerably.

Traders should monitor official tournament draws and any late withdrawals through the ATP or ITF announcement channels. Injury reports, weather delays affecting scheduling, and last-minute player substitutions could trigger the 50-50 resolution clause if the match extends beyond seven days without completion. Recent tournament disruptions across North American summer circuits have increased the relevance of delay provisions in settlement terms.

Methodology

We track Granby: Justin Boulais vs Zhizhen Zhang 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.

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.

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.