NEW YORK (AP) Three races in a five-week span at varying distances on different tracks. It's so tough only 11 horses have won the Triple Crown, and none in 36 years.
It's the longest span without a winner. Now it's California Chrome's turn to try on Saturday at the Belmont Stakes.
The striking chestnut colt with a blaze and four white feet appears to have rebounded well after two hard races in the Kentucky Derby and Preakness, with the most exhausting still to come. He'll run 1 1/2 miles around Belmont's sweeping oval with 10 rivals gunning to keep history from happening.
Before Affirmed swept the 1978 Kentucky Derby, Preakness and Belmont, 25 years had passed between Citation in 1948 and Secretariat in 1973.
Few can agree on what makes winning the Triple Crown so tough. Often it's a combination of factors that help or hurt a horse, including racing luck and jockey error.
In 2002, War Emblem nearly fell to his knees when the starting gate sprang open, and jockey Victor Espinoza knew right then the colt was doomed. He straggled home in eighth place, beaten 19 1-2 lengths by a 70-1 shot.
Espinoza gets another shot on Saturday aboard California Chrome, who, if he wins, will have faced down the largest field of any Triple Crown winner.
''It doesn't matter if there are 14 or six horses. He needs to break clean,'' said Bob Baffert, the only trainer to lose the Belmont three times with horses that won the first two legs, including War Emblem.
California Chrome had been slow out of the starting gate in some of earlier his races because of his habit of shifting from one foot to the other. Espinoza will try to keep his head pointed straight and get him to show some early speed leaving the gate.
''With a clean break, he's way better than all the other horses,'' said Baffert, who will be watching from Southern California on Saturday.
Trainer Art Sherman often describes California Chrome as a ''push-button horse,'' meaning the colt can respond to whatever Espinoza asks him to do. Tactically, he can run on or near the lead or make a move for the front in the latter stages of a race, like California Chrome did in the Derby and Preakness.
''He's going to probably be galloping on the lead,'' Sherman said. ''He doesn't want any horse passing him.''
California Chrome is clearly the dominant horse in the 3-year-old ranks, having won six straight races and impressively taken charge in the Derby and Preakness. He has given every indication in his gallops and one official workout at Belmont Park during his nearly three weeks in New York that he likes the deep, sandy track.
Unlike at the Preakness, California Chrome hasn't coughed and he's been eating up all his feed - both welcome signs that he hasn't missed a beat in his preparations.
''I just like what I see. He looks so darn good,'' Sherman said. ''People have a lot more respect for this horse than they did going into the Derby. I really think he's the real McCoy.''
The 1 1/2-mile distance could catch up with California Chrome, whose modest pedigree suggests he can't do what he's already done. Now it's a question of whether he can run an extra quarter of a mile in the Belmont.
Of course, 10 other horses will have a say in what happens Saturday.
''California Chrome is a horse that's going for history, and we're all trying to throw something in his way,'' said Rick Violette, who will saddle Samraat.
Luck - good or bad - plays a big part in winning the triple Crown. Bad luck could befall California Chrome in the form of stumbling out of the gate, getting squeezed or bumped by his rivals or being ganged up on by other horses.
Sometimes jockey error proves costly, too. Riders aren't used to 1 1/2-mile races in the U.S., where the focus is on sprinting. Some have mistakenly moved too soon and burned out their horses before the 1,097-yard stretch run. Others have moved too late and let the leaders get away.
''Some horses absolutely do not want to go a mile and a half and some horses thrive on it,'' said Billy Gowan, who will saddle 12-1 shot Ride On Curlin, who was second in the Preakness.
California Chrome figures to control the race - when he moves his rivals will follow and when he hangs back, so will the rest of the field.
''A little bit of luck, a good trip and a fast horse is what it's going to take to beat him,'' Gowan said.