Diego Maradona has successfully undergone an operation for possible bleeding on his brain, his public relations team said.
In a statement released on Tuesday night, the 1986 World Cup winner's PR handlers said the operation "was all successful and it happened as expected".
Maradona, who played for the likes of Napoli, Barcelona and Boca Juniors before hanging up his boots in 1997, is set to remain in a clinic in La Plata, south of Buenos Aires, for at least 48 hours as he recovers.
Argentina's all-time leading scorer Lionel Messi took to Instagram on Wednesday to wish his compatriot well.
Alongside a picture of the pair together, the Barcelona forward wrote in Spanish: "Diego, all the strength in the world. My family and I want to see you well as soon as possible. A hug from the heart!"
Leopoldo Luque, the 60-year-old Argentinian's personal physician, said following Maradona's admission to hospital in Buenos Aires on Monday it was not an "emergency situation".
He was quoted by Argentinian television's ESPN F90 as saying: "I didn't see him as I would like to see him.
"We need to be calm. This is not an emergency situation. Diego is well, but he could be better.
"You see some situations that make you believe that it is good to come to a clinic, to hydrate, draw blood.
"Let's see how many days. Let's see how much can be done. My idea is to have at least three days for him to hydrate well. It's looking at what's best for him. There is no emergency.
"I told him: 'Diego, you come here'. He said no because he had to manage and I told him to come along so that later he would be able to play.
"I've seen Maradona when he's bad. When he's bad he does not accept help. Sometimes you have to push him a little more and this was one of those times.
"For now he is convinced. How am I going to bring him if not?
"Maradona is not well psychologically and, as with everyone, that affects him physically."