Serena Williams overcame the sixth seed Caroline Wozniacki 6-1 6-4 to progress to the semi-final of the China Open.
Venus Williams continued her run of form in Tokyo with a battling 6-3 6-7(4) 6-3 win over Canadian hope Eugenie Bouchard.
Lucie Safarova of the Czech Republic won her fifth WTA title when she edged New Zealand's Marina Erakovic 6-4 6-3 in Quebec.
Marina Erakovic and Lucie Safarova won semi-final matches on Saturday to advance to the singles final of the Bell Challenge in Quebec City.
Order of play for day eight of the US Open, with Roger Federer, Victoria Azarenka, the Williams sisters and the Bryan brothers on court.
Sara Errani became the highest seed to be knocked out of this year's US Open, losing 6-3 6-1 to fellow Italian Flavia Pennetta.
Order of play for day four of the US Open, with Rafa Nadal, Roger Federer, Serena Williams and Victoria Azarenka all on court.
Round-up: The Maria Sharapova-Jimmy Connors partnership got off to a rocky start as Sloane Stephens shocked the Russian.
Round-up: Laura Robson withdrew from the WTA Toronto event, moments before she was to go on court to face Yanina Wickmayer.
Third seed Maria Sharapova suffered a huge shock defeat at the hands of world number 131 Michelle Larcher de Brito at Wimbledon.
Round-up: Maria Sharapova beat Kristina Mladenovic 7-6(5) 6-3 to move into the second round at Wimbledon on Monday.
Caroline Wozniacki came from a set down to beat Ekaterina Makarova in the quarter-finals at Eastbourne but Li Na is out.
ATP World Tour Finals
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