Rising young star Sir Gino, who was odds-on for the Arkle Chase at Cheltenham, will miss the rest of the season.
A dismayed Nicky Henderson revealed the brilliant five-year-old is in equine hospital after complications following a leg wound suffered last week.
Sir Gino was forced to miss an intended run at Newbury on Saturday with what was described as a “small wound” on a hind leg, but that injury has now become infected and Sir Gino is being treated in an equine hosptial.
The dejection felt by Britain's most successful Cheltenham Festival-winning trainer will be shared by all racing fans, as Sir Gino had looked something out of the ordinary when winning on his chasing bow at Kempton over Christmas.
Henderson said on his X feed on Monday afternoon: "Unfortunately Sir Gino’s situation has deteriorated somewhat and he has been admitted to the Equine hospital.
"As a result of initial examinations at Donnington Grove an infection has invaded the ligaments in his near hind leg. This will require lengthy treatment that will sadly rule him out of any further racing this season.
"This is a dreadful blow to Joe & Marie Donnelly and everybody at Seven Barrows but we will be doing everything possible to help this incredible bright light back to full fitness next season."
Sir Gino was ruled out iof the Cheltenham Festival last season days before he was scheduled to line up as a hot favourite for the Triumph Hurdle.
He was withdrawn because a number of Henderson's horses were under the weather. Star performers Constitution Hill and Jonbon were among others who missed the meeting, and the yard, most unusually, suffered a rare Festival blank.
More to follow