US Open, Qualification WTA: Katie Swan vs Mary Stoiana

Platform comparison

Market context

Katie Swan against Mary Stoiana sits in the US Open women’s qualifying draw, with Swan having already beaten Katrina Scott 6-3, 6-1 and Stoiana having come through her opener against Harmony Tan 6-4, 6-3 before this meeting was scheduled for 26 August[3][7][15]. Stoiana arrived with the cleaner recent run on paper, including a WTA 125 title at Evansville in July and a set of qualifying wins through August, while Swan’s summer has been defined more by survival than volume, following her long injury comeback and a straight-sets loss to Madison Keys at Wimbledon[2][4][9][13].

The 0% crowd-implied probability looks more like a stale or unavailable market than a strong read on the matchup, because both players had already advanced in qualifying and the draw itself was live on the official schedule[3][8][15]. Comparable cases at this stage usually turn on whether the match is actually completed and whether either player withdraws between rounds, since the market can still settle 50-50 if the contest is not played, ends level, or remains undecided by the long-stop date.

For traders, the main catalysts are late order-of-play changes, any injury or retirement reports, and whether either player is pulled into a revised schedule after other qualifying matches run long[3][8]. Stoiana’s recent workload has been heavier, with back-to-back matches in Cincinnati and the US Open lead-in, while Swan’s recent competitive minutes have been lighter but shaped by her return from injury, so any official update on fitness or withdrawal would matter more than ranking noise[2][4][11][13].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Sports-specific comparison page for US Open, Qualification WTA: Katie Swan vs Mary Stoiana. Polymarket's live quote (Polygon order book) plus platform attributes for the three reference venues. Sports markets reward liquidity — Polymarket and Betfair are materially deeper than Kalshi or Manifold.

Resolution & payout

Sports markets typically settle on official final-whistle plus league confirmation. Polymarket uses UMA Optimistic Oracle with a source URL per contract — usually official league data feeds or ESPN/Soccerway. Two-hour dispute window, then smart-contract payout in USDC.

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