The standard saying in racing is that “it’s the horse, not the jockey,” and that even a top rider contributes just 5 to 10 percent of a runner’s performance.

Still, it pays to pay attention to who’s riding your horse today, and of course, most horseplayers do. They know that some jockeys perform better on speed horses than stretch-runners, on turf better than dirt, in sprints better than routes. They know some riders are willing to squeeze through along the rail, while others prefer the outside path. Certain trainers prefer certain jockeys, and their horses are considered either live or not well-meant depending on who’s named to ride.

A switch in riders can be an important handicapping factor. When a trainer goes from a jockey he doesn’t use often to his usual go-to guy, or switches from lesser-regarded reinsman to one of the leading riders at the meet, it can signify the horse is ready for a top effort.

Here are some rider changes on today’s card at Aqueduct that could make a difference:

FIRST RACE: In this New York-bred special weight, But has raced five times, was usually well-bet and turned in some solid efforts, but she’s still a maiden. Today, after showing speed, then tiring, in her first race on turf, the 3-year-old filly returns to dirt. But most important, trainer Ramon Hernandez names Edgar Prado to replace bug boy Lorenzo Lezcano in the saddle.

SECOND RACE: Won Moro, claimed by Greg Martin last out after winning for $7,500 at The Meadowlands, steps up to $12,500. Big M shippers have done well this fall at the Big A, and Won Moro, after being ridden by Carlos Marquez Jr. in Jersey, attracts the services of hot-riding Norberto Arroyo Jr., who’s won three of his last five starts.

FIFTH RACE: In his last start at The Meadowlands, Viva Pentelicus just missed in a similar $35,000 claimer on turf while ridden by Ramon Dominquez. Today, for the first time he’ll be ridden by Aqueduct’s leading rider John Velazquez, who’s been on fire at this meet riding 25 percent winners.

SIXTH RACE: Jockey Rich Migliore has long been the main man for trainer John Kimmel. Here Kimmel gives the Mig a leg up on his 2-year-old Carson City colt City Sharpster, who’s coming off a layoff after finishing a well-bet fourth in his debut last June at Monmouth Park under Robby Alvarado.

SEVENTH RACE: High Commissioner broke his maiden by 4 3/4 lengths going a mile at Aqueduct last April, then placed in a pair of stakes at Woodbine. Unraced since June, he goes a mile again against “non-winners of two lifetime,” and trainer Jim Bond goes to Prado, who has replaced Jorge Chavez as the barn’s go-to guy.