Former Ryder Cup captain Bernard Gallacher is critically ill in hospital, NHS Grampian have confirmed.
The 64-year-old is being treated in Aberdeen Royal Infirmary.
It could not reveal any other details about his condition.
George O'Grady, chief executive of the European Tour, said: "We are in touch with Bernard's wife, Lesley and the Gallacher family, and, obviously, we join with everyone in wishing Bernard a speedy recovery."
His nephew, Stephen, who pulled out of the ISPS Handa Wales Open during the second round this morning due to a back injury, said: "I understand that he is critical but stable. My family is in disarray at the moment and it is obviously a worrying situation. We are all anxious."
Gallacher became a professional golfer in1967 and was named the Sir Henry Cotton rookie of the year in 1968.
A year later he became the youngest winner of the prestigious PGA Championship at 20 years and 97 days, a record which stood until earlier this year when Italian Matteo Manassero triumphed at Wentworth aged 20 years and 37 days.
He now plays the European Seniors World Tours, and had his first senior win at the Mobile Cup in 2002.
Gallacher lives in Berkshire and is the father of three children, including Sky Sports News presenter Kirsty Gallacher.