"Eusebio's body will be brought to the stadium later today and all fans will be able to say goodbye," the spokesman said.
Two of Portugal's stars in recent years were quick to pay tribute to Eusebio as Luis Figo and Cristiano Ronaldo both took to Twitter to hail the achievements of the Benfica legend.
"The king! Great loss for all of us! The greatest!," wrote Figo, who retired in 2009 with a national record of 127 caps to his name, while current Portugal captain Ronaldo wrote: "Always eternal Eusebio, rest in peace."
Chairman of the Football Association in England Greg Dyke said Eusebio was among the best-known international footballers during the peak of his career.
"He was the [Lionel Messi] or Ronaldo of his time," Dyke told the BBC News Channel.
"Every generation has great footballers. He was clearly a world-class footballer who scored an awful lot of goals. He had a level of natural talent that most players don't have."