Olympic champion Andy Murray suffered a second pre-US Open setback in as many weeks when he was knocked out of the Cincinnati Open in the third round on Thursday, losing 6-4 6-4 to France's Jeremy Chardy.
Rafael Nadal withdrew from the US Open on Wednesday increasing concerns about the seriousness of the knee injury plaguing the 11-times grand slam winner.
Petra Kvitova overcame a mid-match slump to claim her first title of the season with a 7-5 2-6 6-3 victory over China's Li Na in the Montreal Cup on Monday.
China's Li Na moved one win away from claiming her maiden title of 2012 after staging an impressive comeback to defeat Czech Lucie Safarova 3-6 6-3 7-5 in the semi-finals of the Montreal Cup on Sunday.
Fourth seed Serena Williams won the women's singles gold medal after beating Russia's third seed Maria Sharapova 6-0, 6-1 in the London Olympics tennis tournament on Saturday.
Former French Open champion Li Na of China was shut out of the Olympic tennis tournament, 6-2, 6-3, by Daniela Hantuchova of Slovakia on Saturday.
Olympic champion Rafa Nadal's withdrawal from the London Games because of injury deprived the tournament of one of its biggest attractions and left Spain reeling on Thursday.
Younger Williams ties sister's record for most titles, now will head back to London for the Games.
The Chinese contingent, led by the nation's first major winner, Li Na, hopes to do better than the lone doubles bronze it won in 2008.
A seventh Challenge Cup secured, Roger Federer was ready for a week's holiday on Monday before returning to London to complete what he hopes will be a unique Wimbledon-Olympic double triumph at the All-England Club.
A number of celebrities came to watch the final on Sunday.
Factbox on Switzerland's Roger Federer who won a record-equalling seventh Wimbledon men's singles title on Sunday.