It was not exactly a "where were you when you heard..." kind of moment. How could it have been on the afternoon when the memorial service for the 7/7 victims was being held at Westminster Cathedral and we heard the predictions that 51,000 had died in Kashmir and thousands more could freeze to death? After such a day, ensuing headlines, which included the words "a nation mourns", were wholly disproportionate.
Yet from those who were inveigled into Best Mate's life, the children who attended Henrietta Knight's open days, to those who profited handsomely from the bay gelding's exploits at Cheltenham, the grim bulletin which reached their ears on Tuesday was a shocking one.
And count among them those of us often cynical professionals who had spent time with that idiosyncratic pair, the engaging trainer Knight and her jovially bucolic husband Terry Biddlecombe - the only man you'll ever meet to make a profanity sound welcoming - at their Oxfordshire stables, and who had also been lured into instinctive membership of the Best Mate supporters' club like victims towards a Venus Fly-Trap.
For many racehorses, it is a pampered life, and an easy death. Easier than for most humans. But whether it was a heart attack or ruptured artery which ended the 10-year-old's life at Exeter racecourse, in what was intended to be his seasonal preparatory race, it was premature. He may have attained the zenith of his achievements with that doughty performance to claim a third Cheltenham Gold Cup in 2004, equalling the feat of the mighty Arkle 40 years before, but he deserved an attempt to by-pass that record.
Jim Lewis, invariably tearful, in victory or defeat, but the kind of owner you would demand if you were a racehorse, reflected: "He'll always be that beautiful horse to me. He'll be up there in the sky now, taking on Arkle - and he'll probably beat him."
The "A" word always surfaced when Best Mate was talked up, even though comparisons between different generations of racehorses are as relevant as contrasting a Best with a Rooney, whose times were roughly as far apart, four decades. Arkle, bred in the same area of north Co Dublin as Best Mate, and invariably referred to as "Himself", will always represent the pinnacle of National Hunt achievement because he was to some extent a genetic freak. As we are reminded in a new book on Arkle*, though he was well-bred through his grandfather, the brilliant Italian horse, Nearco, his father, Archive, never won a race in his 11 attempts.
The Duchess of Westminster's horse, who was initially dismissed as "gangly" and "moving bad" by staff at trainer Tom Dreaper's yard, progressed to win 27 of his 35 races. They included three Cheltenham Gold Cups, two Hennessy Gold Cups, a Whitbread Gold Cup, an Irish Grand National and a King George VI Chase. In handicaps, he ended his career often carrying 12st 7lb and conceding stones to lesser opponents.
Maybe jump racing's greatest understatement were the words Dreaper uttered to his wife, Betty, after Arkle won his first race, a hurdle at Navan: "Do you know, I think we've got something there . . ."
Arkle's career came to a premature end on the racecourse, too, though he survived to enjoy some retirement. It was at Kempton after his attempt to claim a second King George VI triumph. In one of those quirks of coincidence, his closest rival in the betting was Woodland Venture, partnered by one Terry Biddlecombe. That combination fell two from home, and Arkle, whose powers appeared strangely depleted under jockey Pat Taaffe, finished second. The courageous steeplechaser had run most of the race with a broken pedal bone in his foot.
Just as 39 years later, messages expressing sorrow arrived at Knight's stables, so letters and gifts in their hundreds began to be sent to Dreaper's yard, expressing hope that Arkle would recover. One was apparently from his old adversary, Mill House. Though he never raced again, Arkle lived another three and a half years before being put down humanely after suffering from arthritis.
Between that era and Best Mate's, we have thrilled to the adventures of that Grand National scrapper Red Rum and the Irish mare Dawn Run and, of course, the grey Desert Orchid, who, though his presence on the racecourse could be almost like a ghostly apparition, his victories were all too real.
Now we seek a worthy successor to Best Mate. In the long term, it could even be Knight's Racing Demon, who won the following race on Tuesday. More immediately, we should probably look no further than last season's King George and Gold Cup victor Kicking King, trained - again coincidentally - by Pat Taaffe's son Tom; or another grey, Iris's Gift, or Trabolgan.
But as we do so, we remember a horse who made reputations, like that of Best Mate's now retired jockey, Jim Culloty, and who changed lives. And none more so than that of the "odd couple", Knight and Biddlecombe; even in their sorrow they know they have been blessed.
* Arkle: The Life and Legacy of "Himself", by Sean Magee (Highdown, £20)Reuse content