Benfica president Luis Filipe Vieira led the tributes to Mario Coluna following the former Portugal captain's death at the age of 78.
Coluna passed away in his native Mozambique on Tuesday, the Primeira Liga club confirmed.
A Benfica legend, he made 677 appearances for the club across 17 seasons, scoring 150 goals and twice winning the European Cup.
In addition, the midfielder earned 57 caps for Portugal and captained the team at the 1966 World Cup in England.
A statement from Vieira on Benfica's official website paid a glowing tribute to the impact made by Coluna.
"It is not easy to say goodbye to someone whose life was among the greatest," read the statement, "Someone whose life path is unique and whose legacy will endure far beyond him. It is said that we are born equal. Untrue! Coluna was born different, for the better, much better.
"He was and will always be a football genius, who magnified football and projected Sport Lisboa e Benfica to a global dimension.
"Coluna gained in life the admiration of those who had the privilege of watching him play, but also the respect and recognition of those who, not having the opportunity to see his football, through reports and testimonies know he was one of the greatest talents of his generation.
"Thank you Coluna! For all you left us.
"Coluna will always be with us. He will be present in our days because he earned that right, with his example and achievements!"
Coluna's death comes little more than a month after the passing of Eusebio, another Mozambique-born star who went on to represent Benfica and Portugal with distinction.
FIFA president Sepp Blatter offered his condolences in a message from his official Twitter account.
"Portuguese football has sadly lost another legend in Mario Coluna," said Blatter.
"My thoughts are with his family and Portuguese football fans."