Milos Raonic and John Isner were knocked out of the Valencia Open by lower-ranked opponents on Wednesday, denting their chances of clinching one of two remaining berths at next month's World Tour finals in London.
Eighth-seeded Canadian Raonic lost his first-round match against Luxembourg's Gilles Muller 7-5, 7-6, while American Isner, the fifth seed, was beaten 7-6, 4-6, 6-4 in the second round by Belgian 21-year-old David Goffin, who reached his third Tour quarter-final of the season.
Seventh seed Marin Cilic of Croatia improved his chances of a spot in London when he cruised past unseeded Spaniard Fernando Verdasco 6-1, 6-4 in the second round.
Cilic will play Ivan Dodig in the last eight after the Croatian qualifier beat former World No. 1 Lleyton Hewitt of Australia, a wild card at the indoor hard court event, 6-1, 3-6, 6-2.
Defending champion Marcel Granollers of Spain won his first round match against Czech qualifier Jan Hajek 7-5, 6-4.
Top seed David Ferrer plays his second-round match against unseeded Spanish compatriot Albert Ramos on Thursday.
Ferrer, the World No. 5, has already qualified for London along with Roger Federer, Novak Djokovic, Andy Murray, Rafael Nadal and Tomas Berdych.
Photograph: Lintao Zhang/Getty Images