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MASON, Ohio — Roger Federer lost another three-set match and, perhaps, his longtime grip on No. 1.
The world's top-ranked player had another out-of-character setback on Thursday, a three-set loss to Ivo Karlovic that left the Croat exulting on his back and opened the way for Rafael Nadal to take over the No. 1 spot by winning the Cincinnati Masters championship.
Nadal stayed on course for the seismic shift by beating Tommy Haas 6-4, 7-6 (7-0) later Thursday, reaching the quarterfinals with his 31st consecutive win. Three more wins and the top spot in the world rankings belongs to him next week.
Even if he doesn't win the championship in Cincinnati, he can pile up enough points to overtake Federer in the next few weeks.
“I know I'm in good position,” Nadal said. “In truth, I don't think about it too much.”
Federer has been ranked No. 1 since Feb. 2, 2004, a record of 235 consecutive weeks. He and Nadal have held the top two spots since July 25, 2005. They will swap if Nadal extends his run of five consecutive tournament titles.
Asked about the possibility, Federer said, “I don't care.”
He's got bigger concerns.
Since his epic five-set loss to Nadal at Wimbledon, Federer has lost in the second round in Toronto and failed to make the quarterfinals in Cincinnati, where he won the title last year. The 26-year-old Swiss star has been struggling to regain his aura of domination since he started the year with mononucleosis.
Nadal has taken advantage by improving his hard-court game and surpassing Federer on the court if not in the rankings.
There was nothing great about his few days in Cincinnati.
Federer needed three sets to get through his first match. Then, he lost for the first time in his career when he didn't drop a game on his serve. He simply couldn't crack Karlovic's tough serve.
Federer had won the six previous times he faced the 6-foot-10 Karlovic, but their matches were close. Federer had won 13 of those 15 sets, although nine ended in tiebreakers.
Appropriately, two of their three sets on Thursday ended in tiebreakers, as well. Using his overpowering serve, Karlovic got the best of them both.
Third-seeded Novak Djokovic also advanced to the quarterfinals, beating Andreas Seppi 6-1, 6-2 to set up a rematch with Gulbis. Djokovic beat the Latvian in three close sets during the quarterfinals of the French Open.
