About This Market
ShareTatjana Maria vs. Marta Kostyuk — WTA Tennis match held on 2026-04-18. Review the historical prediction market odds from Kalshi, Polymarket, and more on Prediction Hunt.
Live prediction market odds for Tatjana Maria vs. Marta Kostyuk. Compare prices across Kalshi and Polymarket.
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MARKET RESOLVEDKalshi / Polymarket
Resolved 2026-04-18
This market resolved on 2026-04-18. Marta Kostyuk was the officially declared outcome. Prior to resolution, the market peaked at 99%.
Tatjana Maria vs. Marta Kostyuk — WTA Tennis match held on 2026-04-18. Review the historical prediction market odds from Kalshi, Polymarket, and more on Prediction Hunt.
| Candidate | ![]() | ![]() |
|---|---|---|
Marta KostyukWINNER | 99% | 100% |
Tatjana Maria | 1% | 0% |
Tatjana Maria vs. Marta Kostyuk was a prediction market event tracked across 2 platforms (Kalshi, Polymarket). Marta Kostyuk led the market at 99% implied probability before resolution. Other contenders include Tatjana Maria at 1%.
Marta Kostyuk held the lead at 99% implied probability heading into resolution. Behind Marta Kostyuk, Tatjana Maria at 1% were the next closest contenders. Platforms were tightly aligned at a 0.9% spread, suggesting broad consensus on the odds.
Here were the closing odds across Kalshi, Polymarket: Marta Kostyuk: 99¢ on Kalshi, 100¢ on Polymarket. Tatjana Maria: 1¢ on Kalshi, 0¢ on Polymarket. Platforms were tightly aligned at a 0.9% spread, leaving little room for cross-platform arbitrage.
A price of 99¢ meant the market estimated a 99% chance that Marta Kostyuk would be the outcome. Traders who bought at 99¢ and held through resolution received $1.00 per share — a 1% return on their position. Those on the wrong side received $0.
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Official settlement criteria, resolution sources, and edge cases across Kalshi and Polymarket.
KalshiIf Tatjana Maria wins the Kostyuk vs Maria professional tennis match in the 2026 WTA Rouen Semifinal after a ball has been played, then the market resolves to Yes.
The following market refers to the Kostyuk vs Maria professional tennis match in the 2026 WTA Rouen Semifinal after a ball has been played. If the match does not occur (signaled by a ball being played) due to a player injury, walkover, forfeiture, or any other cancellation (all before the match starts), the market will resolve to a fair price in accordance with the rules. If this match is postponed or delayed, the market will remain open and close after the rescheduled match has finished (within two weeks).
PolymarketThis market refers to the tennis match between Marta Kostyuk and Tatjana Maria in the Open Capfinances Rouen Metropole, originally scheduled for April 18, 2026 at 9:30AM ET. This market will resolve to 'Marta Kostyuk' if Marta Kostyuk advances against Tatjana Maria. This market will resolve to 'Tatjana Maria' if Tatjana Maria advances against Marta Kostyuk. 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. If the match ends in a walkover (player withdraws before the start and the other advances automatically), this market will resolve to 50-50. The primary resolution source will be official information from the WTA Tour. A consensus of credible reporting may also be used.
Marta Kostyuk
99.5% avg