4:55 PM PT -- Herjavec's lawyer, Lee Hutton, tells TMZ, "The allegations are false and with the sole intent for monetary gain. My client has had enough and will not tolerate extortion."

The ex-girlfriend of "Shark Tank" star Robert Herjavec has fired back at him with her own lawsuit, claiming he repeatedly raped and sodomized her.

Danielle Vasinova filed suit hours after Herjavec filed a lawsuit against her, claiming she tried extorting him for $20 million by making false claims in the wake of the Harvey Weinstein scandal.

In her lawsuit, she says Herjavec took her to a secret, underground sex club in L.A. in 2015 and told her to watch him as he engaged in sexual conduct with other women. She claims he then demanded she participate, and when she refused he became angry and overpowered her, pinned her to a table, violently disrobed her, forcefully grabbed her face and jaw to hold her down and engaged in "injurious sexual intercourse and sodomy."

She claims there were other instances of sexual assault. Vasinova says in February 2015, Herjavec shoved her inside from a balcony, threw her down violently across a table and raped her.

And she says, the next morning, in a fit of aggression, he grabbed her by the throat, prevented her from breathing freely and engaged in sexual intercourse.

She claims when they got together he had promised to marry her and take care of her financial needs and pressured her into putting her career on hold.

Vasinova is suing for sexual battery, domestic violence, and infliction of emotional distress.