Only 12 thoroughbreds have achieved the feat in the past century, but Justify's rivals are already conceding it will take a minor miracle to stop him winning the most coveted prize in horse racing.
At this weekend's Belmont Stakes on Long Island, the 150th anniversary of the New York race, Justify has the chance to join the exclusive stable of Triple Crown winners after triumphs at the Kentucky Derby and Preakness Stakes earlier this year.
Mike Smith and Justify target Triple Crown
Would be 13th Triple Crown winner with victory at Belmont
Trainer Bob Baffert sees similarities with 2015 winner American Pharoah
The chestnut colt would become just the second horse to win the esteemed Triple Crown since 1978, with the great American Pharoah the most recent to complete the sweep in 2015.
Justify will run from the rail after drawing the unfancied No. 1 post -- one trainer Bob Baffert always likes to avoid -- but it will take more than that to stop him.
"I think, like all of us, we need Justify to wake up on the wrong side of the bed to have a chance," said Todd Pletcher, trainer of fellow starters Vino Rosso and Noble Indy.
While American Pharoah charged to glory from post five, past Triple Crown winners from No. 1 include Citation (1948), Assault (1946), Gallant Fox (1930) and Sir Barton (1919).
Footsteps of Pharoah
For Baffert, victory for Justify would see him become the second trainer ever to have two Triple Crown horses to his name.
"This horse is starting to act like Pharoah," said Baffert of Justify, which recently became the first Derby winner in 136 years that did not to race as a two-year-old.
"I think I see a lot of resemblance in these two, the way they move ... When I worked him after the Preakness, American Pharoah, when he would breathe, he was like he was a machine. And this horse is getting there."
The story so far
Justify, ridden by 52-year-old Mike Smith, won a rain-soaked Kentucky Derby ahead of Good Magic in May, before handing Baffert a record-equaling 14th race win in the second of the three Triple Crown events at the Preakness just two weeks later.
While each of the three races date back to the second half of the nineteenth century, the concept of the Triple Crown wasn't conceived until several decades later.
Gallant Fox became the first horse to popularize the term with his success in 1930, although it was Sir Barton in 1919 that first won the three races in the same year.
American Pharoah's 2015 victory put an end to a 37-year Triple Crown drought -- a period that saw 13 horses fall short at the Belmont.
Smith and Justify, however, are hot favorites to win in New York on Saturday and write their names into racing's history books.
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