Louis van Gaal has announced he is receiving treatment for prostate cancer.
Speaking on Dutch TV show Humberto, the Netherlands head coach said he had been battling the condition for some time and has undergone 25 rounds of radiation treatment.
Van Gaal, 70, oversaw two international friendlies with the Netherlands last month, with his team beating Denmark 4-2 and drawing 1-1 with Germany.
The former Manchester United, Barcelona, Bayern Munich and Ajax boss said he kept his diagnosis hidden from his players, and revealed he was snuck into hospital to undergo private treatment during the international break.
Van Gaal told presenter Humberto Tan he had wanted his players, who have qualified for the World Cup, to stay focused on their task in hand.
“You don’t die from prostate cancer, at least not in 90 per cent of the cases,” he said.
“It is usually other underlying diseases that kill you. But I had a pretty aggressive form, got irradiated 25 times. Then you have a lot of management to do in order to go through life.
“I did have preferential treatment in the hospital. I was allowed in through the back door when I went to an appointment and was immediately pushed into another room. I have been treated wonderfully.
“You will of course tell your friends and relatives about it. The fact that nothing has come out yet also says something about my environment. That’s great.”
Van Gaal, who had announced his retirement in 2019, was appointed coach of his country for a third time in August last year, taking over from Frank de Boer after the Netherlands’ last-16 exit from Euro 2020.
He was first in charge between 2000 and 2002 but stepped down after failing to secure qualification for the World Cup.
He returned for a second stint in 2012, guiding his nation to third place at the World Cup in Brazil two years later before departing for the Premier League with Manchester United.
A league winner in three different countries, having secured domestic titles while at Ajax, Barcelona and Bayern Munich, Van Gaal has enjoyed a hugely successful managerial career.
He also won the Champions League with Ajax in 1995, then guided Bayern to the final 15 years later.