A judge in Spain has found there is sufficient evidence to rule that a 43-year-old man is the biological son of Julio Iglesias even though the singer refused to have a DNA test.
Julio Iglesias' lawyer Fernando Falomir told CNN the singer would appeal the ruling and said Iglesias wouldn't refuse to submit to a DNA test under certain circumstances as part of the appeals process. The 75-year-old singer did not attend the trial.
Those contacts took place in July 1975, the court heard in the Spanish town of Sant Feliu de Guixols, and "make it not unlikely or unreasonable the possibility that sexual relations existed between them", the ruling said.
The detective managed to get hold of a water bottle that the singer's son Julio Iglesias Jr was drinking from when he was surfing in Miami.
But Osuna had argued a new trial was justified as they had "DNA evidence" brought from the United States by a detective. Osuna claimed DNA testing showed that Santos and Iglesias Jr were brothers.
The judge refused to admit the DNA evidence obtained by the detective.
Before the ruling, Preysler, who was Iglesias's wife at the time of the alleged affair, said she believed that if it was proven that Santos was his son, Iglesias would "do his duty as a father because Julio has always been a very responsible person".
He has enjoyed modest success as a singer and DJ.
Santos and her son have fought a three-decade paternity battle with Iglesias.
Iglesias was married to his first wife Isabel Preysler when the affair with is said to have taken place.
Although Julio had refused to provide a DNA sample the judge - who also refused to admit DNA evidence obtained surreptitiously by a private detective working for the claimant and his lawyer - made his decision based on the "obvious physical resemblance" between the musician and Javier and credible evidence provided by Maria of her week-long affair with the singer at the time her son was conceived.