This is a Grade I stakes race which is open to Thoroughbreds of three years or older in age. biggest Thoroughbred race of the year, with a prize of $5 million!

Because of the large prize which can be won, competitors come from all over the U.S. and the rest of the world. Specific restrictions on weight and other factors are imposed to ensure level playing field. Horse must be at least three years in age and there are weight rules for the horses which are based on age. Horse of four years or older must be at least 126 pounds.

Three year olds born in the northern hemisphere and having an official birthday of January 1st are required to carry 122 pounds. Three year olds born in the southern hemisphere and having an official birthday of August 1st are required to carry 117 pounds. Horses born in the southern hemisphere are considered to be younger than horse's born in the northern hemisphere due to the difference in foaling seasons below the equator.

The horse which wins the Breeder's Cup Classic very often will go on to also win the U.S. Horse of the Year. The last four winners of the Breeder's Cup Classic have all done this - Curlin, Invasor, Saint Laim and Ghostzapper, respectively.

The race is traditionally a hard one to predict the outcome of. The competition is very intense and it can be difficult to make an accurate prediction. One notable upset occurred in 1993 when the underdog Arcangues took the purse. The largest upset in the history of the race, this had a payoff of $269.20 for a $2 bet.

Not only do horseracing fans see the best of the best in today's horses, but they also see the world's top trainers and riders. However, due to the popularity of the race and the tough competition, it is not uncommon to see a new trainer take the win.

For instance, D. Wayne Lukas, who has won numerous races in other Breeders' Cup events only has one Breeders' Cup Classic under his belt with 1999's winner Cat Thief. You also see the best of the best in jockeys in the Breeders' Cup Classic with great names such as Chris McCarron, Jerry Bailey, Mike E. Smith and Pat Day having numerous wins in this race.