Edwin van der Sar's agent says the former Manchester United goalkeeper remains "under control" after suffering a brain haemorrhage, adding that he is confident he will recover.
On Friday the former Dutch international, 52, was rushed to intensive care during his holiday in Croatia after he suffered a bleed on the brain.
His former club Ajax, where he recently worked as chief executive, said Van der Sar was in a stable condition, and the 130-times capped international has been receiving well-wishes from around the globe.
Speaking on the KieftJansenEgmondGijp podcast, via the Dutch publication VI.nl, Jansen said: "Of course things are not going well. But not good and good. That's what it's called under control.
"You have to protect the family in this. He's in good hands. Annemarie (his wife) is there with her son. There is continuous contact from the Netherlands about how to proceed."
Elaborating on his client's condition, he said: "He needs to rest very well.
"We are confident that this will work out, but it is not small. A brain haemorrhage is very serious. She (Annemarie) had it herself in 2009. She recognises a lot of what happened to her then."
The incident occurred a month after Van der Sar stepped down from his role at Ajax, which Jansen says he told him to do.
"Edwin and I have had a number of conversations," he said.
"That was weeks before he made that decision. I said then, 'Edwin, you have to stop. This is done. You did what you had to do.' At a certain point you will never get it right again."
Ajax issued a statement after the news on Friday.
"Edwin van der Sar will remain in intensive care for the time being," they said.
"His condition is stable but still concerning. Ajax shares this information on behalf of Annemarie van der Sar, Edwin's wife.
"The Van der Sar family, along with Ajax, is grateful and deeply touched by the many messages of support."
United had earlier tweeted their support, writing "Sending all our love and strength to you, Edwin," while fellow former club Fulham said: "Everyone at Fulham Football Club wishes Edwin a speedy recovery. We're thinking of you."
"Ed is a fighter," tweeted Van der Sar's former United teammate Rio Ferdinand. "Our thoughts are with the Van Der Sar family!"
Former England and Arsenal keeper David Seaman wrote: "Wishing the great man Edwin Van Der Sar a full and speedy recovery, stay strong big man!"
