Argentine number one Juan Martin del Potro has made himself unavailable for the 2013 Davis Cup World Group opener against Germany from February 1-3, captain Martin Jaite said Sunday. "We sent emails to all the players likely to be selected and asked them to respond before December 10. Del Potro didn't answer. On December 20, he then sent me an SMS to tell me that he was not available," Jaite told La Nacion. "The relationship with Del Potro isn't broken, the doors of the team are always open to him." Without world number seven Del Potro, Argentina may struggle to progress in the Davis Cup where this year they were beaten 3-2 in the semi-finals by eventual champions, the Czech Republic.