Resolution criteria on PolyGram: This market refers to the tennis match between Hikaru Shiraishi and Hiromasa Koyama in the ITF Men Karuizawa, originally scheduled for May 28, 2026 at 9:00PM ET. This market will resolve to 'Hikaru Shiraishi' if Hikaru Shiraishi advances against Hiromasa Koyama. This market will resolve to 'Hiromasa Koyama' if Hiromasa Koyama advances against Hikaru Shiraishi. 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.
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
| ITF Karuizawa: Hikaru Shiraishi vs Hiromasa Koyama | 0% YES | 100% NO |
| Completed Match | 100% YES | 0% NO |
Hikaru Shiraishi faces Hiromasa Koyama in an ITF Men's tournament match scheduled for 28 May 2026 at Karuizawa. The current order book on Polymarket shows zero probability for Shiraishi, reflecting either minimal trading activity on this lower-tier ITF fixture or a consensus view favouring Koyama. ITF tournaments, particularly those held in Japan, typically attract limited liquidity compared to ATP or Challenger events, which explains the sparse pricing data available to traders.
Both players compete primarily on the ITF circuit, where match outcomes depend heavily on recent form, surface preference, and head-to-head records. Karuizawa's hard court surface and spring timing are standard variables in Japanese ITF scheduling. Without recent match data or ranking movements between these competitors, the zero probability likely reflects insufficient order book depth rather than definitive market intelligence. Traders should monitor ITF rankings and any withdrawal announcements through the official ITF website or tournament draws, typically published one to two weeks before competition.
The settlement window closes 5 June 2026, allowing a one-week buffer beyond the scheduled date. Key catalysts include confirmation of the match proceeding as scheduled, any late withdrawals or injuries, and the actual result. Given the illiquid nature of ITF markets, early positions may face difficulty finding counterparties, and traders should account for potential delays or cancellations common in lower-tier professional tennis.
This market settles from the official outcome published at https://www.itftennis.com/en/tournament-calendar/. 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 "ITF Karuizawa: Hikaru Shiraishi vs Hiromasa Koyama" are the same as any other PolyGram sporting 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.
Resolution is sourced from https://www.itftennis.com/en/tournament-calendar/. 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 5 June 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.
Explore more prediction market odds and trading opportunities on PolyGram: