- Game Spread: Kalieva (-0.5) vs Costoulas (+0.5)>99¢
- US Open, Qualification WTA: Elvina Kalieva vs Sofia Costoulas>99¢
- US Open, Qualification WTA: Completed Match: Elvina Kalieva vs Sofia Costoulas>99¢
This market refers to the tennis match between Elvina Kalieva and Sofia Costoulas in the US Open, Qualification WTA, originally scheduled for August 26, 2026 at 5:00PM ET. This market will resolve to 'Elvina Kalieva' if Elvina Kalieva advances against Sofia Costoulas. This market will resolve to 'Sofia Costoulas' if Sofia Costoulas advances against Elvina Kalieva. If the match is canceled (not played at all), ends in a tie, or a winner has not been determined by September 9, 2026, 11:59 PM ET (14 days after the scheduled start), 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.
Kalieva enters as the higher-ranked player at WTA No. 115 with a recent career-high mark, giving her an edge in this US Open qualifying round-two match on hard courts against No. 155 Costoulas. Both advanced from round one on August 25, with Kalieva defeating Mladenovic in three sets and Costoulas beating Ruggeri in straight sets. The head-to-head is split 1-1, but Kalieva won their only prior hard-court encounter in 2024. Kalieva’s stronger recent hard-court results and home-soil familiarity position her as the market favorite, though Costoulas’s youth and solid 2026 win rate keep the matchup competitive.