Prosecutors say Portuguese football star Cristiano Ronaldo will face no charges in Las Vegas in connection with a 10-year-old sexual assault allegation because the case cannot be proven beyond a reasonable doubt.

Key points: Cristiano Ronaldo and his accuser reached a civil settlement in 2010, until the woman asked police to reopen the investigation in 2018

Cristiano Ronaldo and his accuser reached a civil settlement in 2010, until the woman asked police to reopen the investigation in 2018 Ronaldo has maintained he is innocent of rape

Ronaldo has maintained he is innocent of rape The footballer's attorney and sports agency have yet to comment

Ronaldo, who is widely regarded as one of the greatest footballers of all time and plays for the Italian club Juventus, has maintained he is innocent of rape.

The allegation made headlines last year after Las Vegas police said they were investigating it.

The case stems from a June 13, 2009 call from a woman to Las Vegas police. She reported that she had been sexually assaulted and police took her to the hospital for an examination, the Clark County District Attorney's Office said in a statement.

But she declined to identify the person she said assaulted her.

The woman and Ronaldo reached a civil settlement in 2010 and law enforcement did not hear again from her until August 28, 2018, when she asked police to reopen the investigation.

Cristiano Ronaldo and his accuser reached a civil settlement in 2010, before the woman asked police to reopen the investigation in 2018. ( AP/ANSA: Alessandro Di Marco )

She said Ronaldo was the person who sexually assaulted her, prosecutors said.

"Based upon a review of the information presented at this time, the allegations of sexual assault against Cristiano Ronaldo cannot be proven beyond a reasonable doubt," the District Attorney's Office said in a statement.

Ronaldo's attorney, Peter Christiansen, and a representative for his sports agents could not immediately be reached for comment.

Reuters