STUTTGART, Germany -- One day after winning the Wimbledon title for the first time, Rafael Nadal pulled out of the Mercedes Cup on Monday with muscle pain above his right knee.
The second-ranked Spaniard, who said he won't play again until healthy, traveled to the Weissenhof tennis center to tell the promoters personally of his withdrawal as the clay-court event's defending champion and star attraction.
"This was the least I can do. I'm disappointed that I can't play," Nadal said. "My doctor said I need a few days off. I will have a checkup and treatment and won't return to the court until I am 100 percent fit."
Nadal has played 47 matches since mid-March, winning six titles and reaching another final. He had fought knee problems since before last year's Wimbledon tournament.
"The calendar is hard on us players," he said. "I have played four, five months without a break. I have to recover."
The 22-year-old Nadal dethroned Roger Federer as Wimbledon champion Sunday, needing 4 hours, 48 minutes to hold off the Swiss star's stirring comeback, 6-4, 6-4, 6-7 (5), 6-7 (8), 9-7.
The win was Nadal's first Grand Slam title outside of the French Open, which he has won the last four years.
Nadal remained second to Federer in tennis' world rankings released Monday but has closed the gap. Federer has 6600
points and Nadal 6055.
Federer has led the rankings for a record 232 consecutive
weeks, and Nadal has been second for a record 155.
Nadal withdrew after four seeded players pulled out Friday. The biggest loss was Rainer Schuettler of Germany, beaten by Nadal in the Wimbledon semifinals, who has a right elbow injury.
The tournament hopes the withdrawal problem will be solved next year by a new date which leaves a break between its start and the Wimbledon final.
Organizers were critical of the ATP for where the event was scheduled, but professed sympathy for Nadal's withdrawal.
"He is here today, because he is responsible and has character," tournament director Edwin Weindorfer said. "Every player needs a rest, especially someone like Nadal, who is always in the final."
Information from The Associated Press and Reuters was used in this report.