The investigation was reopened by police in Las Vegas last fall after the woman, Kathryn Mayorga, went public with the allegations in September, claiming Ronaldo - then 24 - raped her in a hotel there after a night of clubbing.
According to the report, the warrant has been sent to the court system in Italy, and once it's served, the Italian officials are expected to collect a sample of Ronaldo's DNA and send it back to Vegas police.
Las Vegas police opened an investigation past year after Ms Mayorga, 33, filed a lawsuit claiming he met her in a nightclub...
Responding to a Reuters query about the report, Laura Meltzer, a Las Vegas police spokeswoman, said in an email the department is "taking the same steps in this case as in any other sexual assault to facilitate the collection of DNA evidence".
A private mediation was organised with representatives of Ronaldo, Mayorga and their lawyers, where she alleges she was paid $375,000 to keep quiet.
The Italian justice ministry, the U.S. embassy in Rome and the Turin police made no comment on the matter, per Sports Illustrated.
But the investigation ended a short time later because Las Vegas police say she only identified her attacker as a European soccer player - not by name - and did not say where the incident took place.
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As you probably recall, the Food and Drug Administration (FDA ) is part of the USA federal government. The report noted that the agency inspected about 19 percent of all food facilities in 2015.
In response to a similar query, Ronaldo's lawyer Peter Christiansen appeared to confirm the DNA request in a separate statement.
Allegri denied the former Manchester United and Real Madrid player appeared concerned after the warrant was made to obtain Ronaldo's DNA on Thursday.
Now, she is looking to help Kathryn Mayorga build a legal case against Ronaldo for sexual assault.
Mayorga, now 34, reported to police that she'd been raped and received a medical examination.
Las Vegas police declined to comment.
The 33-year-old said that Ronaldo "told me if I dated anyone else or if I left my house he'd have me kidnapped and have my body cut up and put in a bag and thrown in a river".
She continued, claiming that Ronaldo has hired publicists, lawyers and investigators to "bully and stalk and harass and frighten and repress" Mayorga.