World No . 1 Gil went through after beating compatriot Rui Machado 4-6 7-6 ( 7-1 ) 6-3 in the first all-Portuguese quarterfinal at an ATP World Tour tournament . Roger Federer reaches semifinals of Estoril Open in Belgrade . Russian star , the 7-1 champion , overcomes slow start to beat Arnaud Clement . Federer Serbia Open title defense ends when he retires in quarterfinal . World No . 2 has been suffering with allergy and fatigue at his home event in Portugal .
World No . 1 Roger Federer reaches semifinals of Estoril Open in Belgrade . Russian star , the 7-1 champion , overcomes slow start to beat Arnaud Clement . Federer Serbia Open title defense ends when he retires in quarterfinal . World No . 2 has been suffering with allergy and fatigue at his home event in Portugal .