Tony Sweeney dies aged 81
He had been taken to St James's Hospital in Dublin last week following a heart attack.
Sweeney was Irish racing correspondent of the Daily Mirror for 42 years and worked as a tipster for The Irish Times since 1988.
He was also a familiar face as part of RTE television's racing team, having been a broadcaster for 35 years.
Jockey Frankie Dettori expects to learn on Wednesday what his punishment will be for failing a drugs test in France in September.