Libema Open: Dayana Yastremska vs Sara Bejlek

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Active sub-markets

Market context

Yastremska, the Ukrainian world number 19, faces Bejlek, a Czech player ranked outside the top 100, in the opening round of the Libema Open grass-court tournament scheduled for 8 June 2026. The 100% implied probability on Polymarket reflects Yastremska's significant ranking advantage and seeding status; conditional tokens on Polygon are pricing this as a heavily favoured outcome, with USDC liquidity concentrated on the YES side. The settlement window extends to 15 June, allowing a seven-day buffer for rescheduling before the market resolves to 50-50 should the match remain unplayed.

Grass-court tournaments historically favour established players with consistent serve-and-volley records, a category Yastremska fits more comfortably than Bejlek. Recent WTA results show players ranked in Yastremska's tier convert opening-round matchups against unranked opponents at approximately 85–90% rates on grass, though upsets do occur. Bejlek's limited tour history and lack of grass-court pedigree further support the current pricing, though qualifiers occasionally produce surprise performances in early rounds.

Traders should monitor official tournament draws, player injury reports, and weather forecasts for the Hertfordshire venue. Any late withdrawal or illness announcement would trigger immediate repricing toward 50-50. Court scheduling changes could affect the match's timing but are unlikely to prevent play entirely. The tight settlement window means delays beyond 7 June without completion would force the market to split evenly, creating tail-risk exposure for YES holders betting on Yastremska's advancement.

Methodology

We track Libema Open: Dayana Yastremska vs Sara Bejlek on the five venues with material liquidity for prediction markets. Live odds come from the Polymarket Polygon order book — the only source that ships real-time data under an open licence. For Kalshi, Betfair and Manifold we list platform attributes (fee, KYC, settlement, payment) instead of fabricated odds, because their APIs use non-comparable contract definitions.

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.

FAQ

Where can I trade this market with the lowest fees?

On Kalshi UK, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Kalshi UK is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

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 it cost to trade on Kalshi UK?

Zero. Kalshi UK routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, Kalshi UK triggers a quick verification flow that finishes in minutes.