Four-time runner-up Novak Djokovic was an easy third-round winner Thursday at the $3 million Western & Southern Open, a hardcourt ATP Masters 1000 event.

Last year's runner-up blew away helpless Belgian David Goffin 6-2, 6-0 at the Lindner Family Tennis Center, where five-time winner Roger Federer upended the Serbian star in last year's finale.

Djokovic's quarterfinal opponent on Friday will be 6-foot-9 American favorite John Isner.

A Day-5 upset came when oft-injured but capable Russian Dmitry Tursunov took out third-seeded French Open runner-up David Ferrer, of Spain, 6-2, 6-4.

Seventh-seeded Argentine slugger Juan Martin del Potro avoided an upset by getting past Spanish left-hander Feliciano Lopez, 6-4, 1-6, 6-4. The 6-foot-7 former U.S. Open titlist del Potro was a hardcourt champ in Washington, D.C., two weeks ago.

Del Potro will meet Tursunov here on Friday.

The recent D.C. runner-up Isner upended 12th-seeded Canadian Milos Raonic, 7-6 (7-5), 6-4, on Thursday. Raonic was last week's Canadian Masters runner-up to the great Rafael Nadal in Montreal.

This is the last Masters tournament before the U.S. Open, which will commence August 26 in New York.

The 2013 Cincinnati champ will collect $583,800.