Rosie Napravnik aboard Mylute. (Reed Palmer / Churchill Downs via AP)

The field for the 139th Kentucky Derby will be set this afternoon, with 20 horses expected to compete in the running for the roses on Saturday.

The field will also feature Rosie Napravnik, bidding to become the first woman to win the race. Napravnik, who leads all jockeys in victories this year, will be riding Mylute and, at the age of 25, has won more than 1,500 races.

“Other jockeys might underestimate my ability to be aggressive in a race,” Napravnik told ESPN’s Kenny Mayne. “Until they ride with me. Then they’re like, ‘Ohhhh, okay.’ ”

Napravnik won the Kentucky Oaks last year aboard Believe You Can.

“She has great hands,” Hall of Fame jockey Mike Smith said of Napravnik. “She gets a horse to relax and do what she wants it to do.”

That involves a little “smooching” sound she makes to a horse, a sound that she declined to make in a “60 Minutes” interview last week. “I have limits,” she said.

The draw is at 5 p.m. EDT on the NBC Sports Network and online at

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