Muhammad Ali's funeral will be held Friday in his hometown of Louisville, Kentucky.
Ali's memorial service is expected to begin at 12 p.m. Arizona time.
Fifteen thousand people are expected to attend an interfaith service open to the public that will be held at the KFC Yum! Center at 2 p.m. Former President Bill Clinton, Billy Crystal, and Bryant Gumbel and his wife, Lonnie, will give eulogies. Also expected to speak is Sen. Orrin Hatch, R-Utah.
Will Smith, who portrayed the boxing legend in "Ali," and former heavyweight champion Lennox Lewis will be pallbearers. The remaining three who will carry Ali's casket are family members.
Poetry will be read by Attallah Shabazz, Malcolm X's eldest daughter, while Valerie Jarrett, a senior adviser for President Barack Obama, will give a statement. Other guests of note include Turkish President Recep Tayyip Erdogan and King Abdullah II of Jordan.
The service will be led by an imam and will include clerics from multiple religions. After the service, a private reception for friends and guests is scheduled at the Muhammad Ali Center in Louisville.
A procession will head through the streets of Louisville, passing through Ali's childhood neighborhood and down a street named after him, as well as by the Muhammad Ali Center and the Kentucky Center for African American Heritage.
Ali will be buried at the Cave Hill National Cemetery in Louisville. Another prominent figure buried there is Colonel Harlan Sanders, the founder of Kentucky Fried Chicken.
Ali was pronounced dead at the age of 74 late Friday night after arriving at a Phoenix hospital to be treated for a respiratory issue days before. His cause of death was "septic shock due to unspecified natural causes," family spokesman Bob Gunnell said. He was surrounded by family when he died.