Assessing which prep races are the best predictors of Kentucky Derby success

In 2012, Wayne Gretzky placed a $50 bet on I'll Have Another in the Kentucky Derby.

Shortly after that, Gretzky, who has dabbled in racehorse ownership in the past with former Los Angeles Kings owner Bruce McNall, told The Globe and Mail's Eric Duhatschek that he knows "a little" about handicapping and liked the colt because he won the Santa Anita Derby, an important prep race for the "Run for the Roses."

I'll Have Another won the Derby at odds of 15-1.

Gretzky is right: The Santa Anita Derby has historically produced horses who have finished well in the Derby. In addition to I'll Have Another, some Santa Anita Derby-Kentucky Derby winners include Affirmed, Winning Colors, Sunday Silence, and most recently, California Chrome. West Coast-based horses in general have fared well in the big race: Ten of the last 20 horses to win the Derby were trained in California.

Yet, racing insiders Ed DeRosa and Christina Blacker aren't as sold on Gretzky's strategy, especially in a year where there is no one standout horse going into Saturday's race.

"Year to year you sort of evaluate the races, and go from there," said DeRosa, who writes for twinspires.com. "But I don't go into any one year thinking one race is going to be better than the other. To me, the preps here are very similar."

Blacker, a West Coast analyst for horse racing television network TVG, agrees. When she's handicapping the Derby, she's looking for a horse with strong "Thorograph" number (a speed figure which calculates how fast a horse has run) and a pattern that suggests the horse is ready for a big effort.

"I want a horse that looks like they are coming into their best race."

However, she says it should come as no surprise that horses that have prepped in California and Florida have historically dominated in the Derby.

"In the case of California and Florida, with the weather, you have the opportunity to train a 3-year-old without interruption, so you can maximize their potential," she said. "And you also have to look at those circuits - you get the best horsemen from New York and the best from Kentucky all heading to Florida, so I don't think it's any coincidence that is where these strong horses are coming out of."

For a horse to run in the Derby, it must first qualify by earning points in one or more of the 35 "Road to the Derby" races across the United States, and at a few international races. The top 20 points earners are offered a spot at the starting gate.

The past few years have produced heavy favorites for the Derby: Last year's winner Nyquist came into the race undefeated, and the year before featured undefeated Dortmund and American Pharoah - the latter of which would eventually win the Triple Crown.

But this year, no one contender overwhelmingly stands above the rest. And horses are seemingly coming from everywhere.

Irish War Cry qualified for the Derby by winning the Wood Memorial in New York, despite the fact that he was based in Florida for the winter. Another strong contender is McCraken, who won the Sam F. Davis Stakes, suffered a minor injury, but then finished third in the Blue Grass Stakes at Keeneland Racecourse in Kentucky.

The Blue Grass was won by Irap, a maiden (who had not won a race prior) based out of California.

Five winners of the Florida Derby have won the Kentucky Derby over the past 20 years. The last time the Blue Grass, a 100-point race, produced a Derby winner was Street Sense in 2007. But DeRosa doesn't consider that when assessing the field.

"The Florida Derby has had a really nice run, and the Arkansas Derby, so when you think you're going back 10 years ... 10 years sounds like a long time but it's only a sample size of 10," he said about the Blue Grass record in determining a Derby winner. "It doesn't bother me."

He doesn't think trainers look at how history has played out in determining which prep races they choose for their horse. It's more about timing and when their horses are ready.

Blacker says that more than simply gauging a horse based on the quality of their particular prep-race fields, she looks for a horse that has faced adversity and shown determination to win, as well as one that demonstrates they will be able to handle all the distractions - the crowds, the noise, and the pressure - of competing in the world's more famous horse race.

It's if they are prepared more than where they prepared, said DeRosa.

"I think in a year where some good horses have lost races like Classic Empire, McCraken and Irish War Cry, to me it's about what performance you've seen you think is good enough to win the Derby," he said.