Take dizzying ride on the jockey-go-round before Kentucky Derby

There are a couple reasons for that, but the main one is that all the top riders show up in Louisville on the first Saturday in May, so it’s not possible to focus on just a couple jocks, as you can sometimes do at an individual track.

Bearing that in mind, let’s run through the many twists and turns that the riders and their agents have gone through to make it onto the starting gate with what they hope is a live mount in the Run for the Roses.

The most interesting twist involves likely favorite Omaha Beach, who was ridden by Flavien Prat in his first five starts, including a nine-length maiden victory on Feb. 2 in his second race after being switched from turf to dirt.

But when the Rebel Stakes was run at Oaklawn Park on March 16, Prat and his agent opted for Galilean, the impressive winner of a California-bred stakes in his previous start. That opened the door for Mike Smith to snag the mount on the Richard Mandella-trained Omaha Beach. Galilean, you will note, is not in the Derby.

Smith was also the regular rider of the Bob Baffert-trained Roadster, but when he threw his lot in with Omaha Beach, Prat was quickly named as his replacement.

Getting an idea of how this works?

Try this one on for size. Jose Ortiz rode Improbable, Plus Que Parfait and Tacitus, but ended up on the latter, the winner of the Wood Memorial Stakes at Aqueduct. That opened the door for brother Irad Jr. to hop on Improbable, jettisoning his previous ride on Win Win Win. Plus Que Parfait’s trainer, Brendan Walsh, quickly secured the services of Julien Leparoux. Win Win Win’s trainer, Michael Trombetta, went back to his colt’s previous rider, Julian Pimental, who was 3-for-4 as a teammate before Ortiz usurped his ride.

Other interesting shifts: John Velazquez rode Code of Honor, Spinoff and Cutting Humor. He sticks with Code of Honor.

Joel Rosario rode Country House, Gray Magician and Game Winner. He sticks with Breeders’ Cup Juvenile winner Game Winner.

Javier Castellano rode Anothertwistafate and Vekoma but sticks with the latter (good idea, given Anothertwistafate is now being pointed for the Preakness Stakes. Manny Franco, who had the mount on Vekoma before being replaced prior to the Blue Grass Stakes, lands on Spinoff, runner-up in the Louisiana Derby.

As of Thursday only two likely Derby starters have not yet been assigned a jockey : the Todd Pletcher-trained Cutting Humor and Peter Miller-trained Gray Magician. Both those should be settled in the next couple of days.

#RJhorseracing featured races

The #RJhorseracing handicappers are off to my old stomping grounds, Golden Gate Fields, on Saturday for two of that track’s marquee races: The $100,000 California Derby, a 1 1/16 mile test for 3-year-olds, and the $250,000 San Francisco Mile, a Grade 3 turf race for 3-year-olds and up.

In the former, the crowd ‘cappers are forecasting a two-horse race, with 2-1 morning line favorite Sparky Ville holding an advantage over 5-2 second choice Kingly. More Ice (8-1) was a distant third in the balloting.

I also think Sparky Ville is the horse to beat, though he has some questions to answer as far as distance and the artificial surface. I like Kingly for second and Visitant (10-1) for third.

In the San Francisco Mile, the crew is convinced that the morning line maker got it wrong and that River Boyne (3-1) should be favored over 5-2 choice Bowies Hero. They have Blitzkrieg (6-1) and Souter (6-1).

“Don’t mind the outside draw with Prat aboard and working well for Mullins,” wrote crowd handicapper Charlie Cronin of the group’s pick.

I have great respect for River Boyne, but I’ve got to take a shot against him with Grecian Fire (15-1), who has some very nice somewhat hidden turf form from Del Mar last summer. I’ll use River Boyne in second and Bowies Hero in third.

Mike Brunker’s horse racing column appears Friday. He can be reached at mbrunker@reviewjournal.com or 702-383-4656. Follow @mike_brunker on Twitter.