Pablo Cuevas hailed "the greatest victory of my career" after seeing off Rafael Nadal in a semi-final epic at the Rio Open.
World number 45 Cuevas prevailed 6-7 (6-8) 7-6 (7-3) 6-4 in just under two and a half hours on the Brazilian clay.
After beating the 'King of Clay' for the first time in his career, Cuevas pointed to a never-say-die attitude.
"This has been the greatest victory of my career, beating the best player in history on clay, so I'm very happy," he said.
"It was a really long match, I wouldn't be able to name one key moment.
"The best thing I did was keep my confidence the whole match. I always believed, being above or below. Even after an hour and a half and losing, I believed that I could defeat him."
Cuevas will face Guido Pella in Sunday's final, but joked he might find something better to do than go after a fourth ATP Tour title.
"I don't know if I'm going to come," he said. "I'm too tired and tomorrow we will have great weather to go to the beach, so...
"No, it will be a difficult match. If he is in the final, it is because he has been playing really well, he won against really good players.
"I need to keep focused as in every other match and go there to battle."