National Bank Open: Learner Tien vs Gael Monfils

Platform comparison

Market context

Learner Tien v Gaël Monfils is priced at a **74% implied probability** for Tien, so the market is treating the American as a clear favourite and Monfils as the underdog. That sits broadly in line with public tennis boards and previews that have Tien favoured in the low-to-mid 1.20s in decimal terms, with Monfils offered as the plus-price side.[14][19]

The basic handicap case leans on form and profile rather than head-to-head history, because there is no prior meeting between them.[2][4][10][12] Tien’s recent record is materially stronger: one source has him at 21–13 in 2026, including 10–6 on hard courts, while Monfils is reported at 4–7 in 2026 and 9–15 over the past 52 weeks.[5][1][19] That makes the favourite case straightforward, but it also leaves some room for a contrarian Monfils ticket if the market is over-weighting raw win rate and under-weighting his experience and past success in Montreal, where he has previously reached the quarter-finals or better five times.[11][18]

For traders, the key catalyst is simply whether the match is played on the expected schedule, because this market carries a 50-50 fallback if it is not completed within the settlement rules.[8] Live draw/order-of-play updates matter here more than usual, alongside any late injury, retirement, or weather disruption that could alter who advances. If the match starts cleanly, the market should largely track Tien’s baseline edge; if there is any delay, scratch, or walkover chatter, the fair value shifts quickly away from the current 74% consensus.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track National Bank Open: Learner Tien vs Gael Monfils 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.

UK Frequently Asked Questions

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.

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%.