Former Cheltenham Champion Hurdle winner Rooster Booster has died suddenly on the gallops.
The 11-year-old grey passed away on Tuesday while being prepared for the Stan James Christmas Hurdle at Sandown on Boxing Day.
"He died of either a haemorrhage or a heart attack. We're not sure yet," said trainer Philip Hobbs.
Rooster Booster won the 2003 Champion Hurdle and was runner-up to Hardy Eustace the following year.
"At least he died enjoying what he did best," said Hobbs. "He was having a gallop ahead of the Christmas Hurdle when it happened."
Rooster Booster was runner-up to Harchibald in that race at Kempton last year.
His regular partner Richard Johnson was devastated on hearing the news.
"It's a big shock. He was a horse that loved life," he said.
"He gave great pleasure, not only to myself but to the owner and to everyone connected with him.
"He gave me one of the highlights of my career when winning the Champion Hurdle. It was a fantastic day and I'll never forget him."