Derrick Rose—the NBA star-player on trial in a civil rape case—testified yesterday that the NBA teaches its athletes how to dispose of used condoms in sex-ed classes as part of its official rookie transition program, according to New York magazine.

The New York Knicks point guard, alongside his two friends Ryan Allen and Randall Hampton, is accused of drugging and raping a 30-year-old woman in her apartment. Criminal charges haven't been brought against any of the men, according to The Los Angeles Times, but police are continuing their investigation into the alleged rape, which was first reported in 2015.

As part of his testimony yesterday, Rose attempted to explain why he would wrap up his used condom and take it with him after a sexual encounter with the plaintiff. To him, walking off with a used condom—rather than putting it in the trash—was simply business as usual, he said, adding that the practice was “kind of normal with my profession” and that the NBA taught him to “make sure you get the condom if you can’t flush it."

Rose said he learned the supposed wisdom of disposing of condoms with semen during the NBA’s official six-day "Rookie Transition Program" in Orlando, Florida; players received “classes on sex,” according to The Daily Beast. The NBA's website describes the orientation as "a series of programs to provide its players with the skills and information necessary for a successful transition to the NBA," including programs on sexual health.

While Rose didn't specify why the NBA would instruct its players to take such a precaution, he did say: "You never know what women are up to nowadays." Rose may have been implying that a woman could use the condom's semen to impregnate herself.

According to the plaintiff, who is referred to only as Jane Doe, the three men slipped something into her drink while they partied at Rose's house. Later, she awoke at her apartment to find the men sexually assaulting her in her room. The plaintiff has said she was drunk, and was in no condition to consent to the sexual encounter.

Rose, a former MVP from his time on the Chicago Bulls, has said that the plaintiff invited the three men to her apartment and encouraged them to have sex with her in turns. The two other defendants—childhood friends of Rose's who now work for him—have not yet testified. "If someone says come in one at a time and you are a guy," Rose asked in part of his testimony yesterday, "then what is that?"

Rose's attorney has asked for a mistrial, alleging the plaintiff's lawyers had withheld text messages she allegedly sent to Rose that bolster the men's account of the night. It's unclear exactly what the text messages say, but the plaintiff's attorney contends they show the woman was incapacitated, while Rose's attorneys claim the messages demonstrate consent.

If the plaintiff's attorney can’t show time-stamped proof by today that he shared the messages with the defense team, the judge has said he will consider granting the mistrial.