Bobs Worth and trainer Nicky Henderson
Bobs Worth took half of his 22 starts under Rules – and his tough nature won him dozens of fans.
Trainer Nicky Henderson told the Racing Post : "You could set your watch by him. He got out of bed, got on with his job and rarely missed a day or had a problem.
"He wouldn't tell you he was as good as he was – unless he was hiding it from me – and he wasn't naturally brilliant, but he just tried ten times harder than any other horse."
Jockey Barry Geraghty, who enjoyed the big days with him at Cheltenham, sold him to Henderson for just £20,000 in 2009.
For winning the Gold Cup, Bobs Worth scooped his team £313,225 alone.
Geraghty tweeted: "It is so sad to hear Bobs Worth passed away this morning.
Celebrations commenced following the 2013 Gold Cup triumph
(Image: The Wharf)
"He was loved and adored by anyone who was ever involved with him since we had him as a youngster to his time @sevenbarrows and in his retirement with Charlie & @wickhamwicks and their boys.
"He was a real star."
Punters and racing supporters recalled their favourite memories of the veteran, who was retired after Cheltenham in 2016.
He had a particular fondness for the track and competed there nine times in the colours of The Not Afraid Partnership.
One person wrote: "Possibly the toughest national hunt horse of this century and my personal favourite. A sad day."
Another added: "Oh no that’s so sad. I saw him win the novice hurdle at the Festival and then the Hennessy, my sincere condolences on your tragic loss."
A third fan tweeted: "Rest easy Bob. 3 time Festival winner who never quite got the credit he so obviously deserved. Tough as teak."