Dual Irish champion Flat jockey Joseph O'Brien is reported to have decided not to ride at all this year and to concentrate on his new role as a trainer.
The move had been widely expected as the record-breaking jockey had been turning his attentions more to the training side and is in the process of taking out a full licence.
O'Brien, 22, has been playing a key role in helping his father, trainer Aidan, with a large string of horses recently from a base at Piltown, Co Kilkenny.
JCB Triumph Hurdle favourite Ivanovich Gorbatov is among those being put through their paces where the great Istabraq's triumphs were originally masterminded.
Tall for a Flat jockey, O'Brien was always likely to find his battle with the scales too much over time.
He is looking to gain his training licence shortly to have runners under Rules and saddled his first point-to-point winner at the beginning of November.
"It's hard enough to make a decent job of one thing never mind trying to juggle two things so I'll be concentrating on training and won't be riding anymore," O'Brien told the Racing Post.
O'Brien can number an array of top Flat horses such as Camelot, St Nicholas Abbey, Australia and many others on his riding CV, twice winning the Derby at Epsom.
His first Classic success came on Roderic O'Connor in the 2011 running of the Irish 2000 Guineas at the Curragh, and he is hopeful of further big-race glory when he oversees Ivanovich Gorbatov in the Istabraq colours of JP McManus at Cheltenham next week.
The son of Montjeu needs to bounce back from an odds-on reverse at Leopardstown last month, but O'Brien feels there is improvement in him.
Speaking at a preview night last week, O'Brien said: "He worked at Leopardstown last weekend and Barry (Geraghty) was very happy with him.
"Nothing came to light after his last run in the Grade One, other than he didn't like the ground. He got away with it first time over hurdles and maybe we got a bit of a false sense of security from that.
"We do think he's a good horse and hopefully on the better ground at Cheltenham he'll show an improved performance.
"The mistake he made in the back straight last time wouldn't have helped him, but we think the biggest problem was the ground."
