The 11-time champion jockey Lester Piggott is in intensive care in a Switzerland hospital following the recurrence of a heart problem.
Piggott, 71, fell ill in December and spent several days in hospital before returning home to recuperate.
His wife Susan and daughter Maureen Haggas are believed to have flown to Switzerland to be at his bedside.
His son-in-law, trainer William Haggas, said: "The latest news we have is that Lester is conscious and coherent."
Piggott retired in 1994 after 4,493 career wins, including nine Derby victories, his first coming in 1954 on Never Say Die.
He was due to attend a special race day in his honour at Newmarket on Saturday, where he enjoyed some of his greatest triumphs.
Members of his family, including his other daughter Tracey and brother-in-law Robert Armstrong, and friends including Sir Peter O'Sullevan and former jockeys Jimmy Lindley and Bruce Raymond were expected to join him.
It is 50 years since the first of Piggott's seven Guineas winners, after whom the races on 'Lester Piggott Day' are named.
The National Horseracing Museum has borrowed pictures, trophies and memorabilia from Piggott's home to create a special display in a racecourse marquee.
希望佢吉人天相，早日康復啦。
