The Gold Cup works hard to keep its secrets, Keith Melrose goes in search of the answers

In racing, the Cheltenham Gold Cup is out on its own when it comes to prior knowledge. Everyone watching on Friday will have seen the King George, 99 per cent last year's Gold Cup, 90 per cent the Savills. When the Grand National rolls around in a few weeks, will you say the same of its key trials like the Bobbyjo or the Ultima?

Yet despite all the attention given to the race, it still keeps more than its share of secrets. This is something that only the uncertainty of sport could provide.

The Gold Cup is often the best trial for itself. What emerges from last year’s running ought to be pretty straightforward – but even here there is mystery. Galopin Des Champs, the central player in Friday's race, did plenty wrong – he raced in the wrong place, he jumped stiffly – but still won convincingly and posted an outstanding Racing Post Rating of 184.