In contrasting styles, China’s Peng Shuai and Frenchman Gael Monfils dominated their more favorite opponents on Day 9 and while Shuai reached the semifinals, Monfils’ theatrical victory over No.7 seed Dimitrov has brought him to face Roger Federer for a semifinal berth. No.2 seed Roger Federer entered his 10th US open quarterfinal in 11 appearances and he was joined by Croatia’s Marin Cilic and Czech Republic’s Tomas Berdych. Denmark’s Caroline Wozniacki was another woman, who made it to the semifinal of US open on Tuesday.