GENEVA — U.S. Open champion Marin Cilic lost in the Geneva Open quarterfinals on Thursday, beaten 7-5, 6-3 by Santiago Giraldo of Colombia.
Cilic, who has been troubled by a shoulder injury this year, has advanced to only one tournament semifinal since winning his first Grand Slam title last September.
The second-seeded Croatian had nine aces on the clay-court surface but failed to create a break-point chance against the 67th-ranked Giraldo.
Giraldo will play Thomaz Bellucci of Brazil or Albert Ramos-Vinalos of Spain in an all-unseeded semifinal.
Top-seeded Stan Wawrinka of Switzerland was set to play Federico Delbonis of Australia in the final match on court Thursday.