It was supposed to be Best Mate's glorious return to racing but it ended in tragedy. The nation's favourite horse collapsed after suffering a fatal heart attack in the William Hill Haldon Gold Cup at Exeter.
Paul Carberry, Best Mate's jockey, tracked the leader Ashley Brook - ridden by Brennan - for the first half of the race on Henrietta Knight's triple Cheltenham Gold Cup winner but he started to nudge the horse on as the leaders moved clear.
Carberry began to ease Best Mate in the home straight, eventually pulling him up, and screens were swiftly erected around the obviously-struggling horse.
Little could be done to save him and his passing will shake the racing world to its foundations.
Best Mate had already won the affections of racing fans throughout the world.
He had not raced in public since finishing second in Ireland last Christmas, but connections had reported all had been well with the tenyearold in his preparations for his reappearance.
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Knight said: "I have ridden a horse before who suffered a heart attack while I was on board and I have to say this looks reminiscent of that. The legs go, they wobble and then they go down.
"I was actually on the track where he came down and I was the first one there. I knew immediately he had died.
"As I saw him go down I knew I was seeing a dead horse and I just wanted it to be over as quickly as possible."
She continued: "I am very proud of him - he looked an absolute picture today on a course he loved. He was a joy to work with and a privilege to train.
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"Obviously I am very sorry for the jockey and for Mr and Mrs [Jim] Lewis [Best Mate's owners], who are distraught.
"It is probably harder for a lot of people watching the race than it is for Terry and I, as we are more used to this sort of thing happening.
"He was a very, very popular horse with a tremendous following and now there is a big vacuum.
"Even this morning he was getting good luck cards in the post - but I suppose we have all got to go one day and at least he didn't do anything terrible like fall or break a leg.
"We will all miss him very much."
Jim Lewis, the staunch Aston Villa fan who raced his beloved horse in the claret and blue of his beloved club, said: "He was a great racehorse - there can have been very few in the world like him.
"He helped us raise thousands of pounds for charity and he made a lot of difference to many people's lives.
"What a pleasure he was to own and how much he meant to me. I will never forget him."
Lewis revealed Best Mate will be buried at Exeter, which might raise some eyebrows considering the horse's greatest moments came at Cheltenham.
"This is where it all began with him," added Lewis.
"He won his first chase here and was never beaten here before today. It seems like the right place.
"This has been a terrible day but I am still very, very proud of him and there won't be many who did what he did."
The news of Best Mate's death was announced to racegoers over the public address system.
Exeter assistant general manager Vicki Robinson said: "It is with great regret that I have to tell you Best Mate has raced his last race at Exeter today.
"Very sadly he died during the race - we offer our deepest condolences to Jim and Valerie Lewis, who have been fantastic supporters here, and to Henrietta and Terry too."
Jockey Jim Culloty, who partnered Best Mate in 18 of his 22 races, including the three Gold Cup triumphs, said of his former charge: "The fact he was as good as he was, as honest as he was, and as consistent as he was, was why the public came to love him and deservedly so.
"Having a name like Best Mate helped too and he certainly put me on the map.
"I gave up riding a few months ago and my one regret was that I wasn't going to be able to ride Best Mate any more.
"I was looking forward to following his career and I thought he had a couple more good years left in him - but it wasn't meant to be."
Edward Gillespie, managing director of Cheltenham racecourse, said: "We are all very shocked here and saddened for everyone in jumps racing. Best Mate attracted so many people to pay attention to the sport who would otherwise not even look at the racing pages.
"He had the most impact on the sport of any horse in the last 40 years, there can be no question of that.
"We don't lose many really high-profile horses in such a way, I suppose One Man of the jumpers would be the first I can remember, but Best Mate was higher profile.
"I feel so sorry for everyone, we waited 40 years for one like him and he was great."
Exeter clerk of the course Barry Johnson confirmed a heart problem had been the cause of death.
He said: "The veterinary surgeon who attended the horse has confirmed it was definitely a cardiac problem - there was nothing they could do for him."
The Grade Two contest went to the Philip Hobbstrained Monkerhostin (10-1), ridden by Richard Johnson to a comfortable four-length success over Kauto Star.