New Wimbledon champion Rafael Nadal has pulled out of this week's Mercedes Cup because of an unspecified knee problem.
The Spaniard travelled to the Weissenhof Tennis Centre in Stuttgart to inform the promoters personally of his withdrawal.
"I'm disappointed that I can't play," he said.
Nadal, world-ranked number two behind Roger Federer, was the clay-court event's defending champion and star attraction.
However, after defeating Federer in Wimbledon's longest ever men's singles final on Sunday evening, doctors have advised Nadal to take a few days off.

Federer overjoyed with Verdasco win
World Tour Finals - Day One
Winning start for Murray at O2
Murray v Del Potro
London calling Murray
ATP World Tour Finals Preview
Djokovic feeling confident
Fleming - ATP had vested interest
We take a closer look at the ATP World Tour Finals and give our verdict on the likely finalists in London.
Novak Djokovic is convinced his hard work will pay off during his World Tour Finals defence.
While Pac Man may have won big in Vegas, others in the world of sport didn't fair so well at the weekend.