Tallon Griekspoor upset No. 1 seed Alexander Zverev 4-6, 7-6 (5), 7-6 (4) in a second-round match at the BNP Paribas Open on Friday. The loss came eight days after Zverev also was the top seed when he was upset by American teenager Learner Tien 6-3, 6-4 in Acapulco, Mexico. Griekspoor collapsed on the court after converting his sixth match point for his first win over an opponent ranked in the top five.