Granby: Justin Boulais vs Zhizhen Zhang

Platform comparison

Market context

The Granby tournament match between Justin Boulais and Zhizhen Zhang, scheduled for 13 July 2026 at 10:00 AM ET, currently trades at 100% implied probability for Boulais to advance. This extreme confidence reflects either strong conviction about the matchup or limited liquidity in the market, both common in lower-tier ATP Challenger events where trading volume remains thin until match day approaches.

Boulais, a Canadian player competing on home soil, carries the advantage of familiarity and crowd support typical of Challenger-level tournaments. Zhang, ranked lower on the ATP circuit, faces the dual challenge of travel fatigue and playing against a locally-backed opponent. Historical patterns in Challenger events show that home-court advantage at this level correlates with roughly 55–65% win probability for the favoured player, yet the market's 100% reading suggests either incomplete information or a significant disparity in current form that traders have already priced in.

The settlement window closes 20 July 2026, allowing a seven-day buffer beyond the scheduled date. Traders should monitor official tournament updates from Tennis Canada and ATP Challenger tour announcements for any weather delays, injury withdrawals, or scheduling changes. Recent Challenger draws have seen increased late withdrawals due to player injuries sustained in preceding weeks, so fitness confirmations from both camps in the 48 hours before play will be critical. Any announcement of either player pulling out or a rescheduling beyond 20 July would trigger the 50-50 resolution clause.

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

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

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 Prediction Today. 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.

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.