The top-ranked player is aiming for his fourth title at the Hamburg Masters, a tuneup for the French Open. His next opponent is Carlos Moya, who upset fourth-seeded Novak Djokovic 7-6 (4), 4-6, 7-5.

Federer had never dropped a set against Ferrer in six previous meetings.

"I didn't serve very well in the second set and he took advantage of it," Federer said. "He is has one of the best returns in the game, I knew it would be a tough match."

The Swiss player broke serve in the first and last game to cruise through the first set.

But the second was tougher for Federer, who made several mistakes while his Spanish opponent raised his game. Federer served for a 5-2 lead, but could not hold and then Ferrer rallied to win the next three games. Serving for the set, Ferrer double-faulted on his first set point before Federer hit a backhand long.

Serving at 3-3 and 30-30 in the third set, Federer hit a sloppy forehand, but it clipped the net and bounced inside beyond Ferrer's reach. It proved to be the turning point, with Ferrer throwing his racket to the ground in frustration. Federer then served out the game with an ace.

"I got lucky on that cord, that was huge at the end," Federer said.

In the next game, Federer wasted four break points before converting to take a 5-3 lead and serving out the match.

"I was feeling very good off the baseline, and I served well in the first and third sets," he said.

Federer, who has won the Hamburg Masters in three of his last four visits, is aiming for his first French Open title to complete a career Grand Slam. Federer has gone four straight tournaments without a title — his worst run since becoming No. 1 in February 2004.

The 19-year-old Djokovic and 30-year-old Moya provided an enthralling match. Moya, a former top-ranked player who dropped to 36th, saved two set points before winning the first.

Djokovic, winner of three titles this season, got the upper hand in the second with his powerful ground strokes, but he fell behind in the third.

Moya served for the match at 5-3, wasted one match point and dropped his serve. Djokovic fought back to tie at 5-5.

Djokovic mixed great winners with too many errors. Serving to force a tiebreaker, he made three straight unforced errors to give Moya three match points. Djokovic saved two, but Moya then hit a forehand down the line. Djokovic got his racket to it, but his crosscourt attempt went wide.