If Agassi wants another shot at the title he won in 1994 and 1999 , he will have to win his semifinal on Saturday against another unlikely American , the unseeded Robby Ginepri , who defeated No . 8-seeded Guillermo Coria of Argentina in the afternoon in another mood-swinging five-set match , 4-6 , 6-1 , 7-5 , 3-6 , 7-5 .