Marta Kostyuk vs Sloane Stephens Prediction (Aug 18, 2026)
Result: Marta Kostyuk won. We gave Marta Kostyuk 95% before the match, so our pick (Marta Kostyuk) was right.
Brier score (lower is better): ours 0.003, market six hours out 0.020.
| Our model | Marta Kostyuk 95% · Sloane Stephens 5% |
| Market price at our call | Marta Kostyuk 86% |
| Event | Cincinnati · Hard |
| Scheduled start | Tue Aug 18, 2026, 02:00 PM ET |
| Call logged | 2026-08-17 15:29 UTC (before first serve) |
Every call we make is logged before the match and graded after it. See the live tennis board, the full match list and our public track record.
All Cincinnati 2026 predictions · Marta Kostyuk predictions · Sloane Stephens predictions
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