Denman, the 2008 Cheltenham Gold Cup winner, died on Tuesday at the age of 18, trainer Paul Nicholls has reported.

Nicholls said the brilliant chaser “had begun to go downhill in the past few days”, and was “put to sleep painlessly”.

The trainer told Betfair: “The decision was taken by his devoted owner Paul Barber with the full support of myself, our head lad Clifford Baker and our vet Buffy Shirley-Beavan.

“We all agreed it was the right thing to do because he had begun to go downhill in the past few days and we did not want to see him suffer.”Denman was renowned for his iron will on a racecourse and won 14 races from 24 starts.

His finest hour came in the 2008 Cheltenham Gold Cup, when he defeated stablemate Kauto Star by seven lengths in a race for the ages.

Denman claimed four Grade One races and was also twice successful in the Hennessy Gold Cup at Newbury in 2007 and 2009. He retired in 2011 and earned over £1million in prize-money.

Nicholls said: “Denman was known affectionately to punters and racegoers as ‘The Tank’, which I always felt was a fitting description.

“He was a magic horse who had a tremendous following because of the wholehearted way he went about his racing.

“He was tough, hardy and willing, wasn’t the easiest to train, and would bite your hand off in his box given half a chance.

“He came along at the right time and was one of our superstars during a golden era for Team Ditcheat.”

Ruby Walsh spoke to Paddy Power about Denman:

Of Denman’s great wins, what was his best ever performance?

Ruby Walsh: “He was an incredible athlete and his second Hennessy Gold Cup win in 2009 was the best weight carrying performance by a horse that I’ve ever been involved in. He was probably a handicap certainty when he won his first Hennessy off a mark of 161, but to win his second off a mark of 174, which was 13lbs higher than when he won it the first time, that was incredible. As good as his Gold Cup win was, what he did in that second Hennessy Gold Cup, off that mark, was amazing.”

When did you first hear of Denman?

RW: “Paul was on about him but I didn’t ride him much early in his career as I was riding at different meetings the days he was running. Christian Williams rode him in the earlier days. The first time I rode him was in the re-arranged Challow Hurdle at Cheltenham but well before then, Paul had been saying that he had this huge big horse belonging to Mr Barber and Harry Findlay that he really liked. Paul kept saying to me ‘this is some horse to gallop’ and he was dead right.”

What was so special about Denman?

RW: “Like for such a big horse, he had such movement of his feet in front of a jump – it was incredible. He was a brilliant horse to ride over a fence and he was just an unbelievable athlete. He had a brilliant career and he was a very good novice hurdler but chasing was always going to be his forte. He excelled over fences. He was unbeaten as a novice over fences and he went unbeaten for a long time over fences. He bolted up in the RSA and his performance in the Hennessy with Sam Thomas was spectacular. I won a Lexus on him and then he beat Kauto Star in a Gold Cup. He was just an incredible racehorse and an incredible athlete.”

Ten years on from his 2008 Gold Cup win over Kauto Star, are you still surprised?

RW: “I wasn’t surprised that Denman beat ‘Kauto’ that day. They were two phenomenal horses to come along at the same time and they had a great rivalry. What Denman did in that year’s Gold Cup was unbelievable and the gallop he went was incredible. To have so many horses beaten so early that day was unbelievable. He was a wonderful horse.”

How do you rate his two Hennessy Gold Cup wins to this day?

RW: “The time he won his first Hennessy with Sam on board, I had a dislocated shoulder and I watched the race in a bookies in Wexford. Visually that day, it was very impressive but I suppose when you look at it, his second Hennessy win, when he won it off a much higher mark and gave so much weight to a Grade 1 horse in What A Friend, technically that was a better performance. To give What A Friend 22lb, who won a Lexus and a Betfair Bowl on his next two starts, was just incredible. To me, that was his greatest ever performance.”

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