Rafael Nadal was forced to skip Wimbledon this year due to tendinitis in his knees.Rafael Nadal was forced to skip Wimbledon this year due to tendinitis in his knees. (Akira Suemori/Associated Press)

Rafael Nadal's sore knees will keep him out of Spain's Davis Cup quarter-final against Germany next month, the team announced Tuesday.

The No. 1 men's player in the world was forced to skip defence of his Wimbledon title because of tendinitis in his knees.

Nadal is the first reigning Wimbledon men's champion not to defend the title since Goran Ivanisevic in 2002 and only the second in the last 35 years.

He was left off the Davis Cup team as Spain's coach Albert Costa announced the matches in Marbella July 10-12.

"[Nadal] is not well and we have to let him rest," Costa said during a news conference.

Costa named Fernando Verdasco, David Ferrer, Feliciano Lopez and Tommy Robredo, plus Nicolas Almagro as a standby.

With files from The Associated Press