The result was not as important for now as achieving "an acceptable level" after a left knee injury forced him to take the longest break of his career, he said on Saturday.
"After spending more than six months without competing, I'm not thinking about becoming No. 1," Nadal said at a news conference in the coastal resort of Vina del Mar.
"It's something that even when I'm in good shape and starting the year I don't plan, so I'm not going to plan it now. My objective now is to go week by week and do the best I can in every game I play."
The 11-time Grand Slam champion said his knee has improved but it still hurt sometimes and he's going to remain "humble and patient" in his comeback. He's also scheduled to play in the Brazil Open in Sao Paulo starting on Feb. 11 and the Mexico Open in Acapulco from Feb. 25.
Nadal is one of the best clay-court players in the history of the game, but he began downplaying his performance in Latin America before he even stepped foot in Chile.
Nadal's first test in the Andean country comes on Tuesday in doubles with Argentine Juan Monaco, followed by his opening singles on Wednesday.
The clay tournament in Vina del Mar is expected to be safe ground in preparation for the French Open, the only one of the four Grand Slams that takes place on clay, and which Nadal has won seven times - more than anyone in history.
Nadal has not played since losing in the second round at Wimbledon in June.
He said he's passed six blood and urine doping tests since then. In the wake of Lance Armstrong's doping scandal, Nadal said he supports strict controls to keep tennis clean.
"We must have certainty that the rival in front is as clean as I am," he said. "I don't have any problem with having controls every week to combat what has happened in other sports. Tennis continues to be a clean sport as it has been throughout its history."
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