National Bank Open (Doubles): Jiang/Wu vs Mertens/Shnaider

Platform comparison

Market context

Polymarket is pricing Jiang/Wu at **0% YES** and Mertens/Shnaider as the market side to beat on this USDC-settled, Polygon-based contract, with the board still reflecting the possibility that the match outcome may already be effectively decided by the time traders can act.[6][16] The contract resolves to the team that advances under the event rules, but if the match is not completed for any reason, or if it is cancelled, tied, or pushed beyond the seven-day window without a winner, it resolves 50-50 rather than to either side.[1]

That kind of zero-print is usually read against the broader market stack, where Tennis.com and several sportsbook-style feeds have consistently shown Mertens/Shnaider as the clear pre-match favourite, often around the low-70s to high-70s in implied probability, while Jiang/Wu have sat in the low-20s to high-20s range.[5][14][19] Comparable Polymarket tennis contracts tend to reprice sharply once live score data, retirement risk, or walkover risk becomes relevant, because the conditional-token structure is tied to whether a winner is actually determined rather than to nominal match staging alone.[1][7]

For traders, the practical catalysts are schedule confirmation, any official walkover or retirement notice, and whether the tie actually reaches completion before the settlement window closes.[1][17] Tournament listing pages and live scoreboards are the fastest checks for whether the match has started, been moved, or been left unfinished, and that matters here because an incomplete match does not resolve to a side on Polymarket.[3][15] On a hands-on Polymarket view, the important distinction is between a genuine advance by either pair and a non-completion outcome that sends value back to the 50-50 resolution bucket.[1]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, which mirrors the Polymarket order book directly.

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.

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 PolyGram. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

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%.