Former Manchester United and Ajax goalkeeper Edwin van der Sar’s condition is “stable but still concerning” following a bleed on his brain, his family says.
The 52-year-old was taken to an intensive care unit on Friday.
He “will remain in intensive care for the time being” said Ajax in a statement on behalf of his wife.
He is reportedly being treated in a hospital in Croatia, where he was on holiday.
The former Netherlands international, who won 130 caps for his country, resigned from his role as Ajax chief executive in May after the side finished third in the Dutch league and failed to qualify for the Champions League for the first time since 2009.
He retired from playing after leaving United in 2011 before joining the Ajax board in 2012, and later becoming the club’s chief executive in 2016.
Van der Sar made 266 appearances for the Red Devils and helped them to win four Premier League titles and the 2008 Champions League.
He also played in the Premier League for Fulham and in Serie A for Juventus.
His former clubs and team-mates are among those sending their support to Van der Sar.
“The Van der Sar family, along with Ajax, is grateful and deeply touched by the many messages of support,” Ajax said.
Football world rooting for Van der Sar – analysis
Simon Stone, BBC Sport’s senior football reporter
Football is united in hoping Van der Sar makes a full recovery.
First as a superb goalkeeper – with Ajax, Juventus, Fulham and Manchester United, plus the Dutch national team – then as an administrator, at Ajax and with the influential European Clubs’ Association, he has developed a first-rate reputation.
I spoke to him in Istanbul, on the day of last month’s Champions League final, when he talked about Andre Onana’s likely influence on the game, Erik ten Hag’s time at Manchester United and also his future plans.
Van der Sar endured a difficult final season with Ajax but, despite leaving the club, gave the impression of someone not intent on staying out of the game for long.
Through the recovery of his wife Annemarie, who suffered a brain haemorrhage when he was a player at United in 2009 and Sir Alex Ferguson, who collapsed in 2018, there are positive examples to reflect on in this uncertain time.
Football is worried on Van der Sar’s behalf. There are many good wishes being extended in public and private as it absorbs this news.
