National Bank Open: Renata Zarazua vs Tamara Korpatsch

Platform comparison

Market context

Renata Zarazua’s first-round meeting with Tamara Korpatsch at the National Bank Open has been priced quite differently across venues: Tennis.com had Zarazua at about 60% projected win probability, while the crowd-implied figure on the contract is 100% YES, implying an effectively unanimous market view in favour of Zarazua advancing.[1][13] That gap is notable because the underlying tennis listings treat the match as an ordinary round-one contest rather than a one-sided walkover, and Tennis Temple’s head-to-head page shows Zarazua leading 1-0, which supports a small historical edge rather than a categorical certainty.[10][3]

Comparable matches between players of this tier often move sharply once line-ups, court assignments and any late withdrawals are confirmed, especially in the opening round of a WTA 1000 event where scheduling is crowded.[1][15] The key trader watchpoint is whether the match is actually played as scheduled and, if so, whether either side is affected by a late change in order of play; the market only resolves to a player if one advances, but a cancellation, tie or delay beyond seven days pushes it to 50-50 under the contract rules. Recent listings from Tennis.com and Tennis365 both still showed the match on 3 August, with Tennis365 giving a 14:00 start time, so any divergence from that timetable would be the main catalyst for a repricing.[1][6]

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 Best Prediction Markets UK, which mirrors the Polymarket order book directly.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

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.

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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Best Prediction Markets UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.