By Jay Privman at Daily Racing Form…

LOUISVILLE, Ky. – As soon as Uncle Mo crossed the wire more than four lengths in front of the field in the Breeders’ Cup Juvenile here at Churchill Downs last fall, he was universally held as the strong favorite for the Kentucky Derby. It was a position he maintained for five months. But the entire perception of this Saturday’s 137th Derby changed on April 9, when Uncle Mo suffered the first loss of his career, in the Wood Memorial.

In the immediate aftermath of that race, trainer Todd Pletcher and owner Mike Repole put out a press release that said Uncle Mo was suffering from a gastrointestinal infection. As a result, Uncle Mo underwent treatment, overseen by Kentucky-based veterinarian Dr. Doug Byars. Uncle Mo’s training schedule had to be adjusted. He has had just two works since the Wood, the first of which was delayed until April 26. Following his final breeze on Sunday morning here, he had an easy jog on Monday, merely walked the shed row at his barn on Tuesday during a driving rainstorm, and just jogged one mile, accompanied by a stable pony, on Wednesday.

The Wood loss, subsequent training schedule, and concerns over Uncle Mo’s ability to handle the Derby’s 1 1/4 miles have made the onetime heavy favorite one of the biggest question marks in this Derby. Another hurdle was added early Wednesday evening, when Uncle Mo drew post 18 in a field of 20 when post positions were drawn for Saturday’s race.

Trainer Todd Pletcher later said he was satisfied with the draw, but his body language told otherwise when the number 18 was called out. He slowly shook his head with a resigned look while sitting alongside Repole.

All this has made the perception of this Derby as being wide-open, not one-sided. Uncle Mo, in fact, is only the second choice on the morning lines of Mike Battaglia of Churchill Downs and Mike Watchmaker, Daily Racing Form’s national handicapper, both of whom made Florida Derby winner Dialed In, who drew post 8, the 4-1 favorite. Battaglia has Uncle Mo at 9-2, while Watchmaker has him at 5-1.

In addition to Uncle Mo, there were several significant developments at the draw, most notably Archarcharch getting the rail, a post that hindered favored Lookin At Lucky in last year’s race. But Archarcharch is best when he drops back and makes one run, so the post might not be as bad as it first looks.

Archarcharch and Comma to the Top were the final two horses to have their posts drawn. Posts 1 and 6 remained. When 6 was called for Comma to the Top, trainer Peter Miller had a beaming smile, relieved his speed horse did not end up on the inside.

By contrast, Nehro, second to Archarcharch in the Arkansas Derby, landed post 19, and Watch Me Go drew the far outside post.

A maximum of 20 horses can run in the Derby, but there were 22 entry slips turned in Wednesday morning. In situations like that, earnings in graded stakes are used to determine the starting field. Sway Away and Ruler On Ice, in that order, had the least in their piggy banks, so they were excluded. There is no also-eligible list for the Derby.

This is the eighth straight year that at least 20 horses were entered in the Derby. If all 20 run, the purse will be $2,196,800, with $1,436,800 to the winner.

With 20 horses entered, two starting gates will be used. Fourteen horses can fit in the main starting gate, and there will be six in an adjacent auxiliary gate.