Roger Federer has often come good at the Cincinnati Masters and the former world No 1 remained on course to win the title for the sixth time, beating Tommy Haas 1-6, 7-5, 6-3.
Federer, who has had one of his least productive summers for years, recovered from a slow start to earn a place in today's quarter-finals against the winner of last night's later match between Rafael Nadal and Grigor Dimitrov. Haas was a break up in the second set but the German was unable to drive home his advantage.
Novak Djokovic coasted to a 6-2, 6-0 victory over David Goffin to earn a quarter-final meeting with John Isner but David Ferrer, who has won only one match since Wimbledon, was beaten 6-2, 6-4 by Dmitry Tursunov.
The 30-year-old Russian will meet Juan Martin del Potro in the first Masters Series quarter-final of his career. Andy Murray faced Julien Benneteau with the winner to meet Tomas Berdych or Tommy Robredo in the last eight.
The US Open begins in 10 days' time, which will be too early for France's Jo-Wilfried Tsonga. The world No 8 has been suffering with a knee injury he sustained at Wimbledon and has been forced to pull out of the year's final Grand Slam event.
The United States Tennis Association has given details of plans for a major redevelopment of the US Open's site at Flushing Meadows. A retractable roof over Arthur Ashe stadium is scheduled for 2017, while a rebuilt Grandstand court should be ready in two years' time and a new Louis Armstrong Stadium, complete with a sliding cover, by 2018.
The cost of the whole project is estimated at $550m (£352m). The work will enable the site to host an additional 10,000 spectators each day, with an extra 100,000 expected over the fortnight.