Novak Djokovic dropped just four games against Paul-Henri Mathieu as he coasted into the third round of the US Open.
Serena Williams won 10 games in a row to defeat countrywoman Vania King and reach the third round of the US Open.
Ana Ivanovic became the second top-10 player to crash out of the US Open as she fell to Czech Karolina Pliskova in round two.
Andy Murray will hope he can at last trust his body when he plays Matthias Bachinger at the US Open on Thursday.
Australian Open champion Stan Wawrinka overcame a mid-match blip to reach round three at Flushing Meadows.
Maria Sharapova survived an attritional battle against Romania's Alexandra Dulgheru to reach the third round of the US Open.
Fourth seed Agnieszka Radwanska became the first major casualty of the US Open when she was dumped out by Peng Shuai.
Lleyton Hewitt was unable to cause another upset at the US Open as he went down in straight sets to Tomas Berdych.
Roger Federer and Stan Wawrinka have been confirmed in Switzerland's team for the Davis Cup semi-final with Italy.
Roger Federer eased into the second round of the US Open with a workmanlike win over Marinko Matosevic.