Olya Sharypova, 23, says Zverev tried to strangle her with a pillow in a hotel room in New York before she fled barefoot in fear of her life.
Screenshots of Whatsapp messages sent by Sharypova and shown to CNN Sport appear to suggest the alleged incident happened on August 23, 2019.
Sharypova described the incident without naming Zverev in an Instagram post Thursday but has confirmed she was referring to him in an interview with Russian outlet Championat.
The 23-year-old Zverev, who was runner-up in this year's US Open, disputes her allegations.
"I very much regret that she makes such statements because the accusations are simply not true," Zve