Former No. 3 Grigor Dimitrov had to come through two rounds of qualifying after all the wild cards were allocated, only to lose his first-round match 1-6, 6-4, 6-2 against Federico Delbonis. Dimitrov's ranking has fallen to No. 47 after a shoulder injury, and he let Delbonis convert all five of his break points.
Damir Dzumhur also came through qualifying and the 57th-ranked Bosnian beat wild-card entry Feliciano Lopez 6-7 (2), 6-4, 7-5 in the first round. Dzumhur will play second-seeded Stan Wawrinka on Wednesday.
Sixth-seeded Adrian Mannarino lost 6-7 (2), 6-3, 6-2 to Albert Ramos-Vinolas. The Geneva tournament and another clay-court event this week in Lyon, France, are the final men's warmups before the French Open begins Sunday.
More AP Tennis: https://www.apnews.com/apf-Tennis and https://twitter.com/AP_Sports