This market refers to the tennis match between Karen Khachanov and Alexander Blockx in the US Open ATP, originally scheduled for September 9, 2026 at 11:30AM ET. This market will resolve to 'Karen Khachanov' if Karen Khachanov advances against Alexander Blockx. This market will resolve to 'Alexander Blockx' if Alexander Blockx advances against Karen Khachanov. If the match is canceled (not played at all), ends in a tie, or a winner has not been determined by September 23, 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 ATP Tour. A consensus of credible reporting may also be used.