Monterrey Open: Camila Osorio vs Ann Li

Platform comparison

Market context

Camila Osorio’s meeting with Ann Li in Monterrey was set as a first-round main-draw match on 24 August, with tournament listings placing it on outdoor hard court and the WTA’s event guide showing first-round play across 23-25 August and the final on 29 August. The market’s 0% YES price implies the contract is already treating an Osorio advancement as effectively impossible, so the relevant question for a programmatic read is not win probability in the abstract but whether the fixture has cleared the “advances” state needed for settlement.

For a trader running this through bots or conditional orders, the important comparator is event completion rather than headline strength. Li entered as the higher seed and higher-ranked player, but the cleanest market interpretation comes from the match state: if the contest was played to completion and Li advanced, the contract should resolve to her; if it was not played, or no winner was determined within the deadline, the fallback is 50-50. Similar tennis contracts often gap sharply once a scheduled match is confirmed to be live, then reprice around late withdrawals, walkovers, retirements and official draw updates rather than pre-match rankings.

The main catalysts are the tournament desk, live scoring feeds and any order-of-play changes published during the first round. Monterrey’s published schedule left a narrow window before later-round play, which means a postponement, suspension or medical withdrawal can still determine whether the market settles on a player name or reverts to the tie rule. For automated approaches, the practical checks are simple: confirm the match was actually started, confirm whether an official result was posted, and monitor for draw replacement or retirement notices before the settlement deadline.

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Methodology

We track Monterrey Open: Camila Osorio vs Ann Li 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

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.

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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.

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