(CNN) Former Nigeria captain and coach Stephen Keshi died Wednesday aged 54 after suffering a cardiac arrest.
Dubbed "Big Boss" by players and fans, he won the African Cup of Nations as both a player and a manager -- one of only two men to do so.
In his playing days, Keshi earned the first of 64 Nigeria caps in 1981, going on to turn out for the likes of Anderlecht and Strasbourg over the course of a distinguished career.
As a coach, he was the first African to lead a team to the last 16 of a World Cup at the 2014 tournament in Brazil.
Former African footballer of the year Kalusha Bwalya was one of many to pay tribute to Keshi, expressing shock and describing his fellow professional as a "football legend."
Nigerian Football Federation president, Amaju Pinnick, describes Keshi as "a superhero," adding his death is a "loss to Nigeria as a nation, not only to Nigeria football."
Former Olympic gold medalist and ex Nigeria coach Sunday Oliseh called it "horrible news." He played with Keshi on the national team and succeeded him as manager in 2015.
"Another legend falls," said Fikile Mbalula, the South African Minister of Sport.