Resolution criteria on PolyGram: This market refers to the tennis match between Calvin Hemery and Ivan Marrero in the Brazzaville, originally scheduled for May 9, 2026 at 11:30AM ET. This market will resolve to 'Calvin Hemery' if Calvin Hemery advances against Ivan Marrero. This market will resolve to 'Ivan Marrero' if Ivan Marrero advances against Calvin Hemery. If the match is canceled (not played at all), ends in a tie, or is delayed beyond 7 days from the scheduled date without a winner determined, this market will resolve to 50-50. If the match begins but is not completed, and one player advances due to the opponent's retirement, default, or disqualification, this market will resolve to the player who advances.
PolyGram is an on-chain prediction market where you trade YES or NO outcome shares with real USDC on Polygon. For this market, buy YES if you believe the event will happen, or NO if you think it won't. Your maximum loss is your stake — winning shares pay $1.00 each at resolution. Unlike sportsbooks, there is no house edge: prices are set by supply and demand from other traders and reflect the crowd's real-time probability.
Market outcomes
| Brazzaville: Calvin Hemery vs Ivan Marrero Set 1 O/U 8.5 | 0% YES | 100% NO |
| Brazzaville: Calvin Hemery vs Ivan Marrero Set 1 O/U 10.5 | 0% YES | 100% NO |
| Brazzaville: Calvin Hemery vs Ivan Marrero Set 1 O/U 9.5 | 0% YES | 100% NO |
| Brazzaville: Calvin Hemery vs Ivan Marrero Match O/U 21.5 | 100% YES | 0% NO |
| Brazzaville: Calvin Hemery vs Ivan Marrero Match O/U 23.5 | 0% YES | 100% NO |
| Brazzaville: Calvin Hemery vs Ivan Marrero Set 1 Winner | 100% YES | 0% NO |
| Brazzaville: Calvin Hemery vs Ivan Marrero Total Sets: O/U 2.5 | 100% YES | 0% NO |
| Brazzaville: Calvin Hemery vs Ivan Marrero Match O/U 22.5 | 100% YES | 0% NO |
Calvin Hemery and Ivan Marrero are scheduled to compete in a tennis match in Brazzaville on 9 May 2026, with settlement contingent on a completed match by 16 May 2026. The current orderbook on Polymarket reflects 0% implied probability for Hemery, indicating the market is pricing near-certain advancement for Marrero or substantial uncertainty about match completion. This extreme skew suggests either material information about player availability, recent form, or head-to-head dynamics that have consolidated trader positioning heavily toward one outcome.
Comparable ATP Challenger and ITF matches in Central African venues show high cancellation and postponement rates, particularly during the May window when weather and logistical constraints affect scheduling. Historical precedent indicates that markets pricing at extreme edges (0% or 100%) on lower-ranked professional fixtures often reflect genuine structural risks—venue stability, travel complications, or player withdrawal—rather than pure competitive assessment. The settlement rules permitting 50-50 resolution if the match is delayed beyond seven days without completion create a meaningful tail risk that sophisticated traders typically price into extreme probabilities.
Traders should monitor official ATP or ITF announcements regarding venue confirmation, player injury reports, and any travel disruptions in the Congo Basin region. Recent scheduling volatility across African tennis circuits has made real-time fixture confirmation critical. The orderbook's current formation at 0% YES warrants scrutiny of whether this reflects genuine match-cancellation risk or simply thin liquidity on a lower-profile fixture; confirmation of both players' participation and venue readiness would be the primary catalyst for probability repricing.
This market settles from the official outcome published at https://www.atptour.com/en/scores/current. A proposer submits the final result to the UMA optimistic oracle on Polygon; the two-hour dispute window closes and payouts clear in USDC.
The mechanics for trading "Brazzaville: Calvin Hemery vs Ivan Marrero" are the same as any other PolyGram event contract. Each YES share resolves to $1 if the event happens, or $0 if it doesn't. The current price between 0¢ and 100¢ is the market's probability estimate, set live by the order book.
$65K in lifetime turnover and $6 of resting liquidity puts this market in the above the median by volume for tennis contracts on PolyGram. Order-book depth is thin — large orders may need to be split across the book or executed as limit orders.
Last 24 hours alone saw $65K in turnover, well above the lifetime daily-average for this market — a clear sign of news catalysing trader activity right now.
The market has been open for under a month — fresh enough that information asymmetry remains a real factor.
Higher-volume markets tend to have tighter spreads and faster price discovery — meaning the displayed YES/NO percentages are more likely to reflect the true crowd-implied probability rather than a single trader's directional view.
Resolution is sourced from https://www.atptour.com/en/scores/current. Settlement is executed by the UMA optimistic oracle on Polygon, with a 2-hour dispute window before payouts clear.
This prediction market is scheduled to close on 16 May 2026. After the resolving event occurs, settlement typically clears within 24 hours once the UMA optimistic oracle confirms the outcome. All payouts are in USDC on the Polygon network.
To trade on this prediction market, create a free PolyGram account at polygram.ink, deposit USDC via Polygon, and place a YES or NO order on the outcome you believe in. You can learn more on our how-it-works page. Your maximum loss is limited to your stake — there is no leverage or margin.
When the outcome is determined, winning YES shares pay out $1.00 each in USDC, while losing shares pay $0. Settlement is handled by the UMA optimistic oracle on Polygon — a proposer submits the result, a two-hour dispute window opens, and if uncontested, payouts are distributed automatically. You can withdraw your winnings to any Polygon wallet.
Prediction-market positions can lose 100% of staked capital. Outcomes are uncertain by definition — historical accuracy of crowd-implied probabilities is high in aggregate but not for any single market. PolyGram does not provide investment advice. Trade only with capital you can afford to lose.
Regulatory status varies by jurisdiction. Germany, the United States, and most EU countries treat Polymarket-style event contracts under one of three frameworks: financial derivative, gambling product, or unregulated novel asset. Consult local counsel before trading.
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