Stockholm:
Germany's Tommy Haas to been forced to quit the Stockholm Open due to a bout of flu, thus handing a quarter-final place to Finn Jarkko Nieminen.
It is the second time in a week the 31-year-old Haas has pulled out of a tournament. He retired after the first set of his Shanghai match against Rainer Schuettler with shoulder pain.
Nieminen, his ranking now down to 120th due to a comeback after spring wrist surgery, will play in the last eight on Friday against the winner from eighth seed Feliciano Lopez and Belgian Oliver Rochus.
Haas also withdrew after seven games into his Montreal second-round match in August against Chile's Fernando Gonzalez.