Overwhelmed with emotion after slugging it out with Puerta for the best part of three and a half hours, Nadal fell back on to the clay court with his arms stretched to the skies.
He then ran across to shake hands with King Juan Carlos of Spain and then clambered over seats to embrace his tearful family in the stands.
"It's unbelievable," he said. "It's a dream come true. I didn't think I was going to cry, but my whole family was very emotional. In the end, I started crying, too.
He became the third Spaniard to win in Paris in four years, joining 2002 champion Albert Costa and 2003 winner Juan Carlos Ferrero.
After being handed the trophy by French football star Zinedine Zidane, Nadal added: "I would like to thank all the people who have supported me the past two weeks. Without them I could not have managed it."
Nadal felled Puerta with a display of withering groundstrokes and phenomenal retrieving to become the youngest grand slam champion since American Michael Chang won at Roland Garros 16 years ago. He has played Wimbledon in the senior ranks only once before, two years ago, when he lost in the third round to American Andy Roddick.
But if Puerta is to be believed, the tennis world must get ready for more amazing feats by the fistpumping Spaniard.
"I think we are talking about someone who is going to write a page in the history of the game," the Argentine said. "I think he's going to do beautiful things in tennis, like Andre Agassi. He's going to become a legend of the game."
