Tommy Robredo won a first-round thriller against Philipp Kohlschreiber in the first round of the Hamburg Masters.
Andy Murray beat Filippo Volandri 6-4, 6-1 at the Monte Carlo Masters to line up a third-round match with Novak Djokovic.
World number two Rafael Nadal led an exodus of seeds at Queen's Club on Friday when swirling winds threw Wimbledon preparations off course for several players.
Former French Open champions Gustavo Kuerten and Carlos Moya slumped to first-round defeats at the Monte Carlo Masters.
Germany's Tommy Haas came from a set down to upset 11th-seeded Andy Murray 2-6, 7-5, 6-3 in Wednesday's fourth round and maintain his impressive run at the Pacific Life Open.
Twice defending champion Andy Roddick raced to a 6-3, 6-0 win over Ivan Ljubicic on day one of the Kooyong Classic.
Unseeded Swiss Stanislas Wawrinka knocked out defending champion Ivan Ljubicic of Croatia 7-6, 6-4 to reach the Qatar Open final.
Top seed Nikolay Davydenko of Russia and second-seeded Croatian Ivan Ljubicic progressed into the second round of the $1 million Qatar Open in contrasting fashions on Tuesday.
Second seed Fernando Gonzalez and defending champion Ivan Ljubicic both suffered quarter-final exits from the Vienna Open on Friday, leaving world number three Novak Djokovic as the tournament's only remaining seed.
Roger Federer beat Ivan Ljubicic 7-6, 6-4 to bring David Nalbandian through with him.
Twice champion Ivan Ljubicic scraped past Mardy Fish of the United States 6-7, 6-2, 7-6 in the Vienna Open second round.
Fernando Gonzalez came back from a set down to beat Ivan Ljubicic 2-6, 6-3, 6-4 and reach the final of the China Open.
World No 7 Fernando Gonzalez stayed on course for his first title of the year a quarter-final victory over South Korea's Lee Hyung-taik at the China Open.
The Indo-Czech duo was beaten 4-6, 7-6, 3-6 in the third round at the US Open.
Leander Paes-Martin Damm will face Mahesh Bhupathi-Pavel Vizner in the quarter-finals of the Montreal Masters.
Russia's Anna Chakvetadze beat injury-hit top seed Jelena Jankovic of Serbia to win the women's title at the Den Bosch Open on Saturday, while Croatia's Ivan Ljubicic beat Dutchman Peter Wessels to win the men's.
Argentine Guillermo Canas tamed big-hitting Croat Ivan Ljubicic 7-5 6-2 to reach the final of the Sony Ericsson Open on Friday, underlining his return to top form following a 15-months doping ban.
Second seed Nadal outfought Argentine Juan Ignacio Chela 7-5 7-5 and third seed Roddick overcame Croatian Ivan Ljubicic 7-6 7-6.
The Russian Mikhail Youzhny brushed aside third seed Ivan Ljubicic to win the World Indoor tournament.
The US Open champions will face either top-seeds Bob and Mike Bryan or the Indo-Czech pair of Bhupathi and Nenad Zimonjic in the semi-finals in Rotterdam.
Croatian top seed Ivan Ljubicic beat Russia's Mikhail Youzhny 2-6 6-3 7-5 on Saturday to set up a final with second seeded Cypriot Marcos Baghdatis in the Zagreb Open.
Ivan Ljubicic inspired Davis Cup champions Croatia to an unassailable 3-0 lead over Austria in the World Group first round.
Top seed Ivan Ljubicic was the only seed to reach the quarter-finals of the Zagreb indoor tournament
The world No 5 Croatian defeated British No 1 Andy Murray in the final.
Britain's Andy Murray knocked out top-seeded Russian Nikolay Davydenko 7-5 6-2 on Friday to set up a final meeting with Croatian Ivan Ljubicic at the $1 million Qatar Open.
Ivan Ljubicic will take on Robin Soederling in Friday's other semi-final.
Ivan Ljubicic said he was reserving judgement on proposed round robin play at ATP tournaments next year.
David Nalbandian thrashed Ivan Ljubicic 6-2, 6-2 to reach the semi-finals of the Masters Cup
He said that experience had taught him how to handle "an incredibly good baseliner" like Nalbandian.
Federer is chasing a third consecutive finale title -- a feat last achieved by Ivan Lendl in 1985-87.
The top-seeded Swiss has lost five times to eighth-seeded Nalbandian but has won their last three matches.
Defending champion Roger Federer was drawn against Guillermo Coria, Ivan Ljubicic and David Nalbandian in the group stages of the Masters Cup.
Top seed Ivan Ljubicic won his third title of the year by beating fifth seed Fernando Gonzalez of Chile 6-3, 6-4, 7-5 in the Vienna Open final on Sunday.
Fernando Gonzalez claimed a 6-4, 3-6, 7-6 victory over third-seeded American Andy Roddick to reach the final of the Vienna Open.
Fifth seed Gonzalez next faces Andy Roddick atthe Vienna Open.
With five weeks to go before the season-ending Masters Cup, six spots in the eight man field remain up for grabs.
The American powered past a below-par Ivan Ljubicic in less than an hour to win the Thailand Open.