Second seed Tommy Haas and No 3 Marat Safin were ousted from the Washington Open.
Rafael Nadal battled past German Tommy Haas 7-6, 6-3 to reach the Cincinnati Masters quarter-finals.
The France-Austria-Britain sequence of races poses a fresh logistical challenge for teams hitherto committed only to back-to-back weekends, with the 21-round season hurrying to the halfway point.
Lewis Hamilton took a big step towards clinching his fifth Formula One title after putting his Mercedes on pole position at the U.S. Grand Prix on Saturday with Ferrari rival Sebastian Vettel starting fifth.
Fernando Alonso hopes to be racing for McLaren at this weekend's Chinese Formula One Grand Prix but the Spaniard says he is taking nothing for granted ahead of a fitness test at the Shanghai circuit. The double world champion fractured his ribs in a crash at the season-opening Australian Grand Prix on March 20 and the governing FIA's medical team then ruled him out of the subsequent race in Bahrain. He will undergo more tests at the Chinese circuit on Thursday before the third round of the 21-race season. "It was disappointing to be told I couldn't race in Bahrain, but I fully respected the decision of the FIA medical team," he said on Tuesday in a team preview for the race. "While I hope I'll be back in the cockpit on Friday (for practice), until I get the all-clear from the doctors to race, whenever that may be, we cannot assume anything.
Roger Federer beat Tomas Berdych in the final in Halle to equal Bjorn Borg's record of 41 wins on the trot on grass
Ferrari's Sebastian Vettel qualified third, ahead of 21-year-old Monegasque team mate Charles Leclerc who was unable to repeat his Bahrain Grand Prix pole of two weeks ago.
Lewis Hamilton led a Mercedes 1-2 at the top of the timesheets for the first free practice session at the season-opening Australian Grand Prix on Friday, while McLaren's hopes of a clean start were tempered by reliability issues.
Andy Murray overcame an ankle injury and staved off two match points on his way to a 3-6, 6-3, 7-6 victory over Haas in the Pacific Life Open.
Finland's Valtteri Bottas took pole position for the Russian Grand Prix on Saturday with Mercedes team mate and Formula One leader Lewis Hamilton having to settle for second place on the starting grid.
Lleyton Hewitt breezed into the last four of the Tennis Channel Open with a 6-2, 6-0 win over Philip Kohlschrieber
The world number one was pushed by the Russian but survived to book his place in the last four of the Australian Open against German Nicolas Kiefer.
Four of Nadal's closest rivals failed to make the last 16, however, as third seed Ivan Ljubicic, fifth seed Nikolay Davydenko, eighth seed James Blake and ninth seed Marcos Baghdatis were upset in their ties.
The top seeds were shocked by Tommy Haas of Germany and Jurgen Melzer of Austria in the \nPilot Pen tournament.
Formula One championship leader Sebastian Vettel pumped in a stunning late lap to snatch pole position from team mate Kimi Raikkonen as Ferrari dominated Chinese Grand Prix qualifying on Saturday.
World number one Roger Federer breezed through to the Halle Open semi-finals with a 6-3, 6-4 win over Germany's Philipp Kohlschreiber.
Spain's Carlos Moya pulled out of next week's Paris Masters on Sunday with a shoulder injury, organisers said.
Top seed Andy Roddick blasted his way into the last four with a 6-4, 6-1 victory over Peru's Luis Horna.
The Briton lapped the Albert Park circuit in a searing one minute and 21.164 seconds to cross the line 0.664 seconds clear of Ferrari's Kimi Raikkonen.
Tennis coach Gavin Hopper was found guilty of charges relating to a teenage girl who attended a school where he taught.
Formula One world champion Lewis Hamilton set the pace in an incident-filled opening Monaco Grand Prix practice on Thursday, with debris and a loose drain cover bringing an early end to the session.
In the semi-finals, Agassi beat German fourth seed Tommy Haas, while Johansson beat fellow-Swede Michael Ryderstedt.
The win was the third of the Finn's career and season, denying Hamilton a 10th of the campaign.
No woman has competed in Formula One since 1976 but organisers of the 'W Series' hope to provide a platform for them to develop skills before taking on the men further up the motorsport ladder. The idea of an all-female series is not new but has been controversial in the past, with top women racers adamant they want to compete against the men rather than be separated.
Sebastian Vettel led a Ferrari one-two at the top of the timesheets in final practice for the Bahrain Grand Prix on Saturday, ending the stranglehold of previously dominant champions Mercedes. Vettel lapped the Sakhir Circuit in a best time of one minute 31.683 seconds, 0.040 faster than team mate Kimi Raikkonen on the supersoft tyres. It was the first time this season that any driver from outside the Mercedes pairing of Nico Rosberg and triple world champion Lewis Hamilton had ended practice on top. Hamilton was quickest in all three sessions in Australia two weeks ago while championship frontrunner Rosberg led his team mate in Bahrain practices one and two on Friday. Rosberg was third fastest in practice three, his time of 1:32.104 slower than Friday when he did 1:31.001, with Hamilton fourth.
The 26-year-old has already done enough to replace Tommy Haas as the\n\nGerman No. 1 when the latest world rankings are released on Monday.
The American No. 2 scored a fluent win over Robert Kendrick U.S. Men's Clay Court Championships.
World champion Lewis Hamilton took pole for Mercedes in qualifying on Saturday for Formula One's season-opening Australian Grand Prix.
'While high-level interventions may help smoothen inter-State relationships, they cannot fundamentally change the alchemy of such relationships, which are firmly rooted in mutual benefits and mutual interests,' points out Ambassador M K Bhadrakumar.
The top seed will face Kenneth Carlsen in the semi-finals after the unseeded Dane beat American Jan-Michael Gambill at the Kroger St Jude ATP event.
The German, winner of the season's first two races, had been second before coming in for a fresh set of tyres while Hamilton won with one stop from pole position.
The German was joined on the front row of the grid by reigning world champion and closest rival Lewis Hamilton, in a Mercedes.
Woods overcame Adam Scott of Australia while Toms beat Peter Lonard \n\nin the semi-finals.