This is a polymarket on the tennis match between Elena Rybakina and Marketa Vondrousova in the 2025 US Open women's singles round of 16, scheduled for August 31, 2025. This market will resolve to 'Rybakina' if Elena Rybakina advances against Marketa Vondrousova. This market will resolve to 'Vondrousova' if Marketa Vondrousova advances against Elena Rybakina. If the match is canceled (not played at all), ends in a tie, or is delayed beyond September 7, 2025 without a winner determined, this market will resolve to 50-50. If the match ends in a walkover (one player withdraws before the start and the other advances automatically), this market will resolve in favor of the player who officially advances to the next round. The primary resolution source will be official information from the US Open. A consensus of credible reporting may also be used.