Simonsig has been put down after he suffered a broken leg during the Shloer Chase at Cheltenham on Sunday.
The 10-year-old grey, trained by Nicky Henderson, sustained the injury when he fell at the third fence.
Simonsig won eight races from 13 starts under Rules in a truncated career that was continually thwarted by fitness issues.
Barry Geraghty celebrates riding Simonsig to victory at Cheltenham in March 2013
Simonsig has been put down after he suffered a broken leg during the Shloer Chase on Sunday
Winner of the Neptune Novices' Hurdle at the Cheltenham Festival in March 2012, he then struck gold in the Arkle Trophy a year later.
Simonsig was sidelined by injury since that final Festival success and only returned to the track at Aintree in November 2015, after which he only raced three more times.
Sprinter Sacre has been retired. The two-time champion chaser won 18 of his 24 starts and amassed £1,136,884 in total prize-money pic.twitter.com/NbbO8wC9iy
— Racing Post (@RacingPost) 13 ноября 2016 г.
Just minutes before the Shloer Chase, a tearful Henderson saluted the Cheltenham crowd after the great Sprinter Sacre paraded following the announcement earlier in the day that he had been retired.
Henderson said: 'It was a hind leg (injury). I thought he was all right when he got up. I can't get this right. You have tears in every single way.
'You all know what the game is like. It tests us, and it is one of those things.
'I've been saying for the last two weeks I would not have worked Sprinter Sacre with him. He has been working too well for Sprinter Sacre.
'They used to go together but he (Sprinter) would not have been able to go with this horse. I thought I got him back.
'Ronnie (Bartlett, owner) adores the horse. The last three months he had not missed one day.
'It (Sprinter Sacre's retirement) was not a funeral, but a celebration of life, but now we've got the funeral and the tears all of a sudden go the other way.
It is not fair for the team more than anything.'