MASON, Ohio, July 31 (UPI) -- Rafael Nadal won his 31st straight match Thursday and moved closer to the world No. 1 ranking thanks to another setback suffered by Roger Federer.
Nadal earned a quarterfinal berth in the Western & Southern Financial Group Masters by downing Tommy Haas 6-4, 7-6.
Federer, who has been on top of the world rankings for four years and five months, was eliminated in the third round by Ivo Karlovic 7-6 (8-6), 4-6, 7-6 (7-5). If Nadal goes on to win this tournament, he will replace Federer as the world's top-ranked player.
Federer has lost three of his last four matches, including the title showdown with Nadal at Wimbledon in early July. He was eliminated in the second round at last week's Rogers Masters in Toronto.
Nadal's winning streak has brought him five consecutive tournament championships.
Novak Djokovic, ranked third in the world behind Federer and Nadal, coasted into the quarterfinals with a 6-1, 6-2 decision over Andreas Seppi. Nicolas Lapentti set up a meeting with Nadal by defeating Fernando Verdasco 6-3, 7-5.
No. 7 seed James Blake was ousted by Ernests Gulbis 6-4, 1-6, 6-3.