Nadal threatens Federer's top spot

CINCINNATI, Ohio: Rafael Nadal shifted into position to seize the No 1 ranking with a 6-4, 7-6 (7/0) defeat of Tommy Haas only hours after Roger Federer opened the door with a Cincinnati Masters defeat.

In the wake of his Thursday's third-round win over the German, Nadal stands three victories away from taking the ATP top spot from Federer. If he claims the title on Sunday, the deal is sealed.

Croatia's Ivo Karlovic defeated Federer 7-6 (8/6), 4-6, 7-6 (5/7) to open the door to the change at the top after four and a half years of Federer's reign.