National Bank Open: Alexander Zverev vs Tallon Griekspoor

Platform comparison

Market context

Alexander Zverev and Tallon Griekspoor are scheduled to meet in the National Bank Open second round, and the market’s 69% price already reflects that Zverev is the clear favourite but not an overwhelming lock. The match is listed as upcoming on Centre Court, with several live and preview pages showing it pencilled in for 5 August in Montreal, which means the immediate risk is still around timing and whether the contest begins as planned.[1][2][7]

The historical frame points the same way: Zverev leads the series comfortably, with one preview putting the head-to-head at 9-2 and noting four straight wins for the German since Griekspoor’s 2025 Indian Wells victory.[12][13] Their most recent meeting, at the United Cup in January, was a straightforward Zverev win, while the National Bank Open’s own archive shows Zverev beating Griekspoor in Montreal in 2023, reinforcing why the market has leaned his way.[8][12][13]

For traders, the main catalysts are the tournament schedule and any late court-order changes, especially with multiple high-profile matches on the same day in Montreal.[4][6][15] Match pages still show the contest as live/upcoming rather than completed, so the key watchpoint is simply whether first-ball is reached without delay; if it starts, the market becomes much more dependent on in-play outcome than on pre-match uncertainty.[1][3][6]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews National Bank Open: Alexander Zverev vs Tallon Griekspoor across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Prediction Today, which mirrors the Polymarket order book at 0% fees.

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.

UK Frequently Asked Questions

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.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.