The most likely is probably John Madden, one of the leading American trainers and breeders of the first half of the 20th century.

Though it would be dangerous to assume that the 2000 Guineas at Newmarket today is a two-horse race, the leading candidates are both excellent examples of the saying. The Aidan O’Brien trained Australia is a son of Galileo – the best sire in the world by many yardsticks – out of Ouija Board, the Lord Derby owned and bred mare who won 10 races in a stellar racing career, with seven of these being at Group/Grade 1 level. Australia is the best of her quartet of winners to date.

Meanwhile, the homebred Kingman is by the Irish National Stud’s Invincible Spirit, a hugely successful sire internationally with winners at the highest level in both hemispheres, and whose sons are now much desired at stud. Kingman is out of Zenda, winner of the French 1000 Guineas and herself a half-sister to the multiple Group 1 winner and sire Oasis Dream.

A little more digging reveals that of the dams of the 14 runners today, exactly half of them were stakes winners, two more were stakes placed, four more won at least once and just one was unraced. Performance is obviously a crucial element in producing high-quality runners. Indeed, studies have shown that the best performed mares produce a higher percentage of top-class runners than their inferiors.

We cannot all aspire to own the best broodmares or to patronise the world’s best stallions, but that should never allow us to compromise on using the best available and the best that we can afford. It is only by doing so that we have any chance to upgrade our stock and, hopefully, produce better class winners. When it comes to the most important races, the evidence is overwhelming.

Naturally, the art of breeding is littered with exceptions and long may this be the case. How boring it would be if we could predict from the outset what the outcome of each crossing of a stallion and mare would produce. Nonetheless, the odds are more in your favour when you use the best performed mares and the best related mares with the most successful racehorses and proven sire lines.

The theory will be tested again over a mile at Newmarket today.