Carballo has been accused by former Olympic gymnast Gloria Viseras of abusing her between 1977 and 1980 when she was between 12 and 15 years old.
However, Carballo broke his silence on the matter in a wide ranging interview and open letter with Madrid sports daily Marca on Saturday, where he denied any wrongdoing throughout his nearly 40 years as a gymnastics coach.
"I emphatically deny all the accusations that have been levelled against me," he wrote.
"I am a good man and I know that in the end I will win, but I know it won't mean anything because this damage is irreparable."
A judge threw out the police's preliminary case against Carballo in April as they had passed the legal prescription limit and concluded the police didn't have sufficient evidence.
However, that decision has been appealed by the Spanish sports council.
Carballo claims that if he had been guilty of any such conduct towards Viseras then it would not have taken such a long time to come to light.
"If this was true, it would not have taken 36 years to come to light.
"It is all a lie. Emphatically, a big, fat lie.
"Her parents came to visit her every day; they were friends of mine, I spoke with them.