LOUISVILLE, Ky. – After a tumultuous prep season in which no horse asserted himself as the clear front-runner of the division, a full field will line up for the 143rd Kentucky Derby on Saturday at Churchill Downs with more questions emanating from this group than a bunch of children in a preschool class.

LOUISVILLE, Ky. – About 1,900 horses reside on the backstretch at Churchill Downs. Every morning, they are groomed, tacked up, and led to the racetrack, where they jog, gallop, or breeze, and then return to their stable.

For a racetracker, the process hardly could look more commonplace. Yet every time the father-and-son training team of Mark and Norman Casse sees a relatively plain-looking bay horse with a white blaze accomplish this mundane task, it eases their minds.

ELMONT, N.Y. – Trainer Graham Motion and jockey Rajiv Maragh have become very close friends over the last few years. It did not have to turn out that way.

In 2011, Motion won the Kentucky Derby with Animal Kingdom, and Maragh finished third on Mucho Macho Man. It was an incident in that year’s Belmont Stakes that could have ended this friendship before it began.

The road to the Kentucky Derby is rarely, if ever, a straight one. The only thing that varies from year to year in this aspect of the journey is how many unexpected detours arise, and how deep into the weeds those detours take us.

This year’s road to the Derby seemed active on both counts. It feels like there were more twists involving important horses than usual. And when things went wacky, it seemed like we wound up in some uncomfortably tall grass, like where someone who wronged Tony Soprano would end up.

LOUISVILLE, Ky. – It was an early-spring morning at Keeneland in 1989 when one of Carl Nafzger’s horses came galloping by, with his newly hired exercise rider impressing the trainer.

“Sharon,” he said, turning to his assistant, Sharon Peters, “don’t let that Australian boy out of my sight.”

The Kentucky Derby field is the most heavily scrutinized of the year in North America, yet much remains unknown about the group until after the race is over.

Most important among the race’s variables is which horses are best able to handle the Derby’s 1 1/4-mile distance, a route of ground no horse in the field will have raced before and most never will again. Since there is no prior form with which to evaluate horses at the classic distance, a useful tool to determine each entrant’s potential is the average progeny winning distance of his sire and dam.

Yes, post position influences the Kentucky Derby, and so does pace.

But estimating the degree of influence is no easy task. While basic considerations of condition, class, and speed figures are pre-race tangibles, the effect of post and pace are uncertain until after both gates open. The main gate is posts 1-14; auxiliary gate 15-20.

IRISH WAR CRY has done little wrong in his five-race career and enters the Kentucky Derby on the heels of an impressive score in the Wood Memorial on April 8 at Aqueduct. Conditioned by Derby-winning trainer Graham Motion, this son of Curlin rebounded nicely following a major flop in the Fountain of Youth on March 4 at Gulfstream. If a line is drawn through that non-effort, you’re left with a colt who is blemish-free and enters the biggest race of his life with the highest last-out Beyer Speed Figure in the field (101).

1. McCraken

2. Always Dreaming

3. Irish War Cry

4. Tapwrit

1. Classic Empire

2. Irish War Cry

3. McCraken

4. Gunnevera

CLASSIC EMPIRE showed his class and talent in winning the Breeders’ Cup Juvenile in fast time last year and then last month exhibited another skill in taking the Arkansas Derby – the ability to overcome adversity. Those traits make him the most likely winner of the Kentucky Derby.