Real Madrid legend Alfredo di Stefano remained in a "serious but stable" condition in a Madrid hospital on Sunday, a day after he went into a coma after suffering a heart attack, the hospital said.

Rescuers battled for nearly 20 minutes to revive the 88-year-old, one of the greatest footballers in history, after his heart and breathing stopped while he was eating with his family near Real's Santiago Bernabeu stadium.

The Argentina-born forward was taken in a serious condition to the Gregorio Maranon hospital which later said he was in a coma, had been sedated and was breathing with the help of a machine.

In a new medical report issued on Sunday, the hospital said he remained in its coronary unit in "a serious but stable condition".

Newspaper El Pais said Di Stefano had been eating with his family when he felt ill and sat down in his wheelchair. By the time an ambulance arrived he was in cardiorespiratory arrest.

"We are all very saddened," Real Madrid president Florentino Perez told journalists late on Saturday after he visited Di Stefano at the hospital.

Di Stefano had been hospitalised seven times for similar episodes, and underwent emergency quadruple heart by-pass surgery after suffering a major heart attack in 2005.

He is one of Real Madrid's most celebrated players, having represented the club for 11 seasons between 1953 and 1964, winning five European Cups. He now holds the title of honorary club president.

The director of Spanish sports daily AS, Alfredo Relano, praised Di Stefano, calling him an "old warrior" in a editorial.

"Fortunately he is immortal. We don't know for how much more time he will be among us, but he leaves much behind. Especially at Real Madrid, whose history he changed," he wrote in a editorial.

Di Stefano was born in Buenos Aires and began his professional career with hometown club River Plate in 1945 before leaving for Colombian outfit Millonarios four years later after the Argentine league ground to a halt following a pay strike.

Di Stefano won the Colombian title in his first season before adding the 1951 and 1952 titles to his list of honours but it was his individual displays that attracted the attention of a host of big-name European suitors.

It was ultimately Real Madrid who won the race for Di Stefano's signature after a long, complicated transfer wrangle with bitter rivals Barcelona.

Di Stefano immediately flourished in the Spanish capital as he helped Real Madrid end a 21-year wait for the league title in his first season before collecting a further seven league crowns during his time at the club.

However, it was on the European stage that Di Stefano truly cemented his status as one of the game's greats, helping Real win the first five editions of the European Cup between 1956 and 1960, a record that stands to this day.

WHen told of the news in Brazil, Argentina striker Gonzalo Higuain, a former Real player, said: "They told me about it in the changing room. It's a tragedy, because of everything that he represents.

"He was always close to me at Real Madrid. I have lots of respect for him and I'm very sad to hear that. I hope he'll recover."