A U.S. judge has dismissed the rape allegation lawsuit made against Cristiano Ronaldo.

Ronaldo was alleged to have raped Kathryn Mayorga in a Las Vegas hotel in 2009, which the Manchester United and Portugal forward has strongly denied. He has never been charged.

Ms Mayorga and Ronaldo are reported to have reached an out-of-court settlement of $375,000 in 2010.

However, Ms Mayorga – who has given her consent for her name to be made public – had been seeking a further payment, stating that she felt pressured to accept the initial offer.

The case was kicked out of court on Friday, though, due to the way the documents relating to the case had been obtained.

U.S District Judge Jennifer Dorsey said in her 42-page order that Ronaldo had been harmed by the conduct of Ms Mayorga's lawyer, Leslie Mark Stovall.

Dorsey said Stovall had worked in "bad faith" through repeated use of stolen and privileged documents to prosecute, which had tainted the case beyond redemption.

"I find that the procurement and continued use of these documents was bad faith," the ruling said.

"Simply disqualifying Stovall will not cure the prejudice to Ronaldo because the misappropriated documents and their confidential contents have been woven into the very fabric of [plaintiff Kathryn] Mayorga's claims. Harsh sanctions are merited."

Ms Mayorga's legal team may yet appeal against the decision.

In a statement released in October 2018, Ronaldo said: "I firmly deny the accusations being issued against me.

"Rape is an abominable crime that goes against everything that I am and believe in."