A Kentucky Derby puzzle: Why the dramatic drop in odds for My Boy Jack?

"It wasn't like the morning line was set poorly," John Asher, the Vice-President for Racing Communications for Churchill Downs, said Monday. "I thought 30-1 was very appropriate for (My Boy Jack)."

Given that many considered the field for the 2018 Kentucky Derby one of the strongest ever in our nation's signature horse race, what explained My Boy Jack going off as the second favorite?

Let's wade through some theories:

— The connections. The brother combination of trainer Keith and jockey Kent Desormeaux combined to run second in the 142nd Kentucky Derby with Exaggerator.

"Kent Desormeaux is a three-time Derby winner," Asher said. "And a lot of people remember what the Desormeaux brothers did with Exaggerator."

— The horse's running style. My Boy Jack is a late-running closer, a horse who hangs near the back early in races, then unleashes one furious late charge to the front.

There is a long Kentucky Derby history of fan fascination with horses who employ that style. The ultimate example was Silky Sullivan, who came to the Derby in 1958 from California as a national folk hero, having once won a race after trailing the leader by 41 lengths.

Alas, at Churchill Downs, Silky Sullivan didn't fire and finished 12th out of 14 horses in a Derby won by Calumet Farm's Tim Tam.

"People fall in love with these late-running horses," Asher said. "They always have."

— The weather. Once it was apparent on what became the wettest Kentucky Derby day ever that the track at Churchill Downs was going to be a sloppy, there was some reason to think that favored My Boy Jack.

In February, he had won the Grade 3 Southwest Stakes at Oaklawn Park on a muddy track.

"If you were looking for a horse that could get over a sloppy track, My Boy Jack was one that had proven he could do it," Asher said.

— The name. By early last week, there were some handicappers touting My Boy Jack as a live Derby dark horse.

Yet it seems likely that the major factor in the odds dropping so dramatically on the horse that was named for the son of co-owner Sol Kumin is that people were captivated by the name My Boy Jack.

"If you had a father named Jack, a brother named Jack, a son named Jack, a friend named Jack, a dog named Jack, any connection to someone named Jack, there's a pretty good chance you might have put a bet down on My Boy Jack," Asher said.

In the 2017 Kentucky Derby, the public became fascinated with Patch, a horse that had only one eye. He, too, started at 30-1 in the morning line before the fans bet him down to 14-1. In this case, the original odds proved accurate, as Patch finished 14th.

"I think that was another example of a horse that the public became captivated with and bet down below (the horse's past form)," Asher said. "The Kentucky Derby is not like other races. You have a very large pool of people wagering who are doing so for reasons other than what the (past-performance) charts are telling them."

My Boy Jack validated the betting public to a large extent with his performance Saturday.

Sitting dead last in the field of 20 after three-quarters of a mile and 16th at the 1-mile pole, My Boy Jack finished fifth in spite of encountering heavy traffic at the turn for home that meant Kent Desormeaux had to guide him wide into the middle of the track to find running room.

"He ran a very credible race," Asher said. "Had he had a little better trip, he may have gotten up to finish on the board."

So along with Justify cutting through the muck, the lasting memory of my 25th straight Kentucky Derby will be the stunning drop in the betting odds on My Boy Jack.

"I've seen my share of Derbys," Asher said, "and I've never seen anything like it."