Source: Ruiz agrees to bout in Saudi Arabia

Fury says Joshua will get KO'd again by Ruiz (0:44)

Tyson Fury says Andy Ruiz knocking out Anthony Joshua wasn't a fluke and explains why he expects the same outcome in the rematch. (0:44)

Unified heavyweight world titleholder Andy Ruiz Jr. has agreed to go to Saudi Arabia to face Anthony Joshua in their much-anticipated rematch, a source with direct knowledge of the discussions confirmed to ESPN on Thursday.

Ruiz and his team on Wednesday night agreed to terms that will have him face Joshua again on Dec. 7 at a soon-to-be-constructed outdoor stadium in Diriyah, Saudi Arabia, where the government is backing a site fee worth tens of millions of dollars.

The Ruiz camp, which includes promoter Tom Brown and adviser Al Haymon, was awaiting the paperwork from Joshua promoter Eddie Hearn of Matchroom Boxing on Thursday, and as long as what they agreed to is reflected in that paperwork, Ruiz will sign, the source said. The Athletic first reported that Ruiz had agreed to terms.

Ruiz's team sought not only a better financial deal than what was spelled out in the contract for the first fight -- about $9 million for the rematch, sources have told ESPN -- but also guarantees for other aspects of the fight that were not part of that original deal.

According the source, Hearn has made Ruiz "happier" in terms of the money, including giving him the Mexican television rights for the bout.

The source also said that the camps agreed to have the Voluntary Anti-Doping Association, widely considered the gold standard in drug testing, oversee random drug testing for the bout. VADA also handled testing for the first fight.

Because Saudi Arabia does not have a true athletic commission with experience regulating professional boxing, another one of the aspects agreed to was that representatives from a United States athletic commission to be determined will be on hand to assist the Saudis in regulating the bout and to make sure normal championship protocol is followed, the source said.

They also agreed that the referee and judging panel will need to have at least 40 world title fights of experience to be considered for appointment, the source told ESPN.

Initially, Ruiz said he wanted to have the rematch in the United States or Mexico and balked at going to Saudi Arabia -- even though the contract he signed for their first bout had a rematch clause that spelled out terms for a sequel and gave Joshua's side the right to determine the date and location of the rematch.

Few expected Ruiz to author one of the biggest upsets in heavyweight history when he took the June 1 bout with Joshua on just a few weeks' notice after Jarrell "Big Baby" Miller was bounced from the fight for failing four random drug tests.

But Ruiz (33-1, 22 KOs), 29, of Imperial, California, survived a third-round knockdown at New York's Madison Square Garden to drop Joshua (22-1, 21 KOs), 29, of England, twice later in the third round. Ruiz scored two more knockdowns in what turned out to be the final round, as he recorded a seventh-round knockout to take Joshua's three major heavyweight titles and become the first fighter of Mexican descent to win a heavyweight world title.

Joshua exercised his contractual right to an immediate rematch, which was expected to take place either at Madison Square Garden again or at Principality Stadium in Cardiff, Wales.

But when Hearn got a massive site offer to stage the bout on the outskirts of the Saudi Arabian capital of Riyadh, he and Joshua agreed to go there, despite the country's reported human rights abuses.

Even though the contract for the first fight spelled out the terms of the rematch, Ruiz would not agree to have the fight in Saudi Arabia until certain stipulations were met.

Hearn, who declined comment to ESPN, recently held a news conference in London with Omar Khalil -- the managing partner of Skill Challenge Entertainment, the company that spearheaded the Saudi Arabian effort to land the fight -- to announce the venue for the bout. Neither fighter attended the news conference, and Ruiz had not yet signed off on going to Saudi Arabia. That resulted in Hearn having little choice but to give in on some deal points to make sure Ruiz would fight in Saudi Arabia.