National Bank Open: Daniel Merida Aguilar vs Learner Tien

Platform comparison

Market context

Polymarket is pricing **Learner Tien at 0% YES** on this conditional-token contract, so the market is effectively saying there is no live probability left on the listed outcome rather than simply assigning him a low chance. On Polymarket, the trade settles in USDC on Polygon, and the contract only resolves once the on-chain event logic is satisfied by the match result, with a fallback to 50-50 if the match is not played, ends level, or is delayed beyond seven days without a winner.

That zero price is much harsher than the pre-match comparison from bookmakers and tennis models, which had Tien as the favourite but not by a margin that would normally imply certainty. OddsChecker listed Tien around -212 against Merida Aguilar at +171, while other pricing screens put Tien near 1.47 to 1.51 decimal and Merida Aguilar around 2.55 to 2.75. Tennis Tonic and String Tension both also pointed to Tien, with the latter giving him a 76.3% win probability on its Elo-style model, so the Polymarket print looks more like a trading artefact or stale book than a pure reflection of pre-match strength.

For a Polymarket user, the key catalysts are straightforward: whether the quarter-final was actually completed, whether any retirement or walkover occurred, and whether the official tournament status was posted in time for settlement before the seven-day deadline. Flashscore and Tennis.com both listed the fixture for 11 August 2026, but if the match was postponed, interrupted or abandoned, the contract can still flip to 50-50 under the market rules. That makes draw status, official ATP score reporting and any withdrawal announcement the only material dependencies now.

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.

UK Frequently Asked Questions

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 Polymarket Alternative UK. 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.

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%.