Fury, determined to put on a show on his Las Vegas debut, overwhelmed Schwarz with a dazzling display of ringcraft before unloading in the second round at the MGM Grand Garden Arena.
The 29-year-old Ruiz started the fight as a massive 32-1 underdog but floored Joshua four times on his way to a win which upended the heavyweight division.
Ruiz recorded a monster upset, by knocking down Britain's Joshua four times to take the World Boxing Association, International Boxing Federation and World Boxing Organization titles.
The call came a week after the International Olympic Committee recommended AIBA be barred from organising the Olympic Boxing tournament because of governance issues.
WBC champion Wilder's decision to fight Ortiz makes it unlikely he will meet rival Joshua in a much-anticipated unification fight this year.
The 60-year-old, currently head of the International Gymnastics Federation, told reporters at a news conference in Tokyo that the call had come out of the blue.
The vaunted knockout artist Wilder swarmed Breazeale from the opening bell, hurting him with a straight right hand then finishing him off later in the round with the devastating right to the chin that was set up by a left jab.
One judge scored the bout 116-111 and two others saw it 115-112 for Williams, who improved to 27-1-1 with 17 knockouts.
AIBA said in a statement to AFP that it will "defend its legitimate right" to organise boxing in Tokyo and "will review all of its options, including legal, given that the IOC has breached the Olympic Charter".
Alvarez kept his World Boxing Council and World Boxing Association titles and seized Jacobs' International Boxing Federation belt in a bout that marked the Mexican's return to the middleweight division.
Alvarez starts as a heavy favorite for a contest that has been notable for an absence of trash-talking and bad blood between its protagonists.
A former WBA and WBO champion in the flyweight division, Estrada improved to 39-3 with 26 knockouts.
Golovkin is scheduled to return to action on June 8 at Madison Square Garden in New York against unbeaten Canadian Steve Rolls
The American has now won nine of his last 11 fights by stoppage.
Sadaf Khadem and her trainer Mahyar Monshipour are currently in the French city of Poitiers, the spokesperson, who asked not to be named, said.