Brazilian soccer great Pele, admitted on Monday to a Sao Paulo hospital for treatment for a urinary tract infection, was moved to a "special care unit" on Thursday, the hospital said.
"Edson Arantes do Nascimento (Pele) remains in hospital. To receive the best care he was transferred in order to be monitored in a special care unit," read a statement released by the Albert Einstein hospital in Sao Paulo.
The hospital said Pele, 74, was suffering "clinical instability," but did not provide details.
However, Jose Fornos Rodrigues, the former player's personal aide, said Pele was "completely fine" and the move was primarily to protect his privacy.
"The problem was that he was receiving too many visitors and that wasn't helping, so they transferred him to a calmer area to continue receiving the proper treatment," Rodrigues said.
"He should be out of the hospital in a few days," the aide said.
A hospital spokeswoman declined to elaborate on Pele's condition, but said he was not in intensive care.
Pele was discharged from the same hospital on Nov. 13 after undergoing surgery to remove kidney stones.
Pele, nicknamed O Rei (the king), was born in a humble home in the city of Tres Coracoes, but is considered by many as the greatest footballer in history with his exploits for Brazil and a career which saw him score 1,281 goals in 1,363 games.
Pele has suffered a long list of health problems in the past decade, including emergency eye surgery for a detached retina and a hip replacement.
Material for this report came from Reuters, AFP and AP.