It's understood that during the interview the suspect admitted he had sex with the woman, claiming it was consensual.
Clothes belonging to the alleged victim were examined as part of the investigation.
The respected young woman had been out socialising on the Saturday and Sunday nights before she met the sports star, who is known to her, and was brought back to the hotel.
The star had been at a separate event in the city, according to sources.
Officers were made aware of the allegations after being called to her south Dublin home.
The woman was then transferred to hospital in an ambulance where she underwent treatment and a number of tests.
She was treated at the Sexual Assault Treatment Unit at the Rotunda Hospital, leading officers to establish that the allegation was credible.