Big Brown has to rise above pedigree to claim Crown

Big Brown, who has scarcely come off the bridle on the march to greatness, is the white hot favourite to answer a nation's yearning in the Belmont Stakes tonight.

But the longest Triple Crown drought in history reflects the increasing toll of the most arduous five weeks in horseracing. Even in the days when horses were bred for durability and stamina, the attrition of their journey was such that none of the previous 11 Triple Crown winners faced more than seven rivals. Affirmed, the last of them, beat four in 1978 – as did Secretariat (1973) and Omaha (1935). Whirlaway (1941) and Gallant Fox (1930) had just three to beat, and even that was one more than Count Fleet (1943) and Sir Barton (1919).

The furore over the candid use of steroids by Big Brown's trainer, Rick Dutrow, guarantees that success against nine opponents in New York would forever be tainted by doubts as to the source of his resilience. He has become a bittersweet symbol of the American sport's moral decay. But the time has come to zoom in from the bigger picture, and decide whether or not he can get the job done – by hook or by crook.

And while Big Brown (above) can plainly run faster over a mile and a quarter than any other American three-year-old, can he stretch that speed over a mile and a half? On the face of it, the leisure of his wins in the Kentucky Derby and Preakness Stakes should have enabled him to conserve more fuel than did War Emblem, Funny Cide and Smart Jones when they failed to complete the sequence in successive years between 2002 and 2004. But the horse has never been foaled that is capable of top-class form without effort. Big Brown has given generously of his reserves and he must now outrun his pedigree, as a son of the sprinting stallion, Boundary.

In contrast, Casino Drive was literally born to win the Belmont. It already stretches credulity that the same mare, Better Than Honour, should have produced successive foals to win the last two runnings of this race, in Jazil and Rags To Riches. But Casino Drive, in turn, looks a formidable candidate, providing he can overcome the late setback of a bruised hoof, having been imported from Japan to win a Grade Two race by six lengths. He will be much fresher than the favourite, but by the same token remains inexperienced.

The each-way recommendation is instead Denis Of Cork, who came from last to third in the Kentucky Derby. His trainer, David Carroll, shrewdly sat out the Preakness in the knowledge that his colt had a much stouter pedigree than that of Big Brown. At odds of 12-1 on the morning line, he will be hard to keep out of the frame and will expose any chinks in the stamina of the favourite.

Few of the 100,000 New Yorkers hoping to witness history today would be grateful for his intervention. Already the American sport is getting ahead of itself. The management of Suffolk Downs yesterday offered a $5m bounty if both Big Brown and Curlin, champion of the previous generation, square up for the Massachusetts Handicap in September. Each colt would receive $1m in appearance money, assuming that both were to arrive in Boston unbeaten in 2008.

The stakes for Big Brown today, already giddy, have now soared even higher.