LOUISVILLE (WHAS11) --One of the suspects arrested in a sting where investigators said the Kentucky Derby was an attractive target for human trafficking pleaded guilty in the case Tuesday.

In federal court, Keith Napier signed a plea deal admitting to asking a 14-year-old girl to help Napier earn money to pay off debts by having the underage girl perform sex acts for various clients.

The girl agreed, according to Assistant United States Attorney Amanda Gregory, and together, Gregory added, the teen and Napier arranged appointments for "out of town clients" at various Louisville hotels between March 2016 and May 2016.

Gregory said Napier knew the girl was underage and utilized the website backpage.com to advertise the illegal services.

Kirsten Logsdon, a woman who was arrested with Napier in 2016 was accused of driving the teen to the Red Roof Inn on Blairwood Road, The Courier-Journal's Matt Glowicki previously reported. The Courier-Journal is a media partner of WHAS11 News.

Logsdon also faces federal charges in the case. She was scheduled for a hearing earlier Tuesday morning.

Because of his guilty plea and conviction, Napier will have to register as a sex offender. He is scheduled to be sentenced September 7. Sentencing guidelines put the range of a possible sentence at 10 years to life in prison.

A press release from the United States Attorney's office updating the investigation was expected later Tuesday.

This story will be updated.

i-Team Reporter Derrick Rose can be reached at 502-582-7232 and dnrose@whas11.com Follow him on Twitter @WHAS11DRose