Jonathan Majors‘ assault trial is heading into its third day and his accuser, Grace Jabbari, will be back on the stand — but this time his attorney will have a chance to grill her about the alleged attack.

The actor’s ex-girlfriend — who is the prosecution’s star witness in the case — is all set for cross-examination from the defense Wednesday … this after testifying Tuesday about her POV of the incident that’s landed them in court.

Most notably, Jabbari backed prosecutors’ assertion she was victimized that fateful night in March — when Majors was arrested and ultimately charged with assault and harassment.

Early Wednesday, she testified she’d taken 2 over-the-counter sleeping tablets on the evening of the alleged assault. She says that’s why she ended up asleep, and half-naked on the bathroom floor at Jonathan’s apartment — and when she woke up, police were standing over her and she could hear Jonathan in the adjacent room.

He’s pled not guilty, and this entire time … he and his attorneys have insisted he was the one who was attacked that night — not the other way around. Prosecutors, however, told a different story in their opening statement … insisting Jabbari had been in an abusive relationship with the guy, which boiled over in brutality in a private car they were in.

Jabbari reiterated that while on the stand, telling her side of the story by explaining she caught JM texting another woman and confronted him about it — snatching his phone away, and then claiming he roughed her up in an attempt to get it back. She also testified that when she tried to flee the car, he grabbed her and threw her inside again … something that was reportedly depicted in surveillance video that the prosecution played for jurors in court.

After their squabble … Jabbari says she went to a party with strangers she’d just met in an attempt to take her mind off things — and while she’s appeared uninjured in photos and videos showing her at the club, GB testified she was actually hurt and licking her wounds.

There were other bombshell moments during her 1st day on the stand, including a recording she’d once taken of Majors during an argument — in which he apparently called upon her to be more like Coretta Scott King and Michelle Obama, while shouting “I’m a great man!”

Jabbari also claimed Majors had been aggressive with her in the past, including one alleged time when she says he lost it on her after she brought up her ex-boyfriend’s doggo.

Majors remained stone-faced during Jabbari’s testimony, which will now pivot to her being questioned by his defense attorneys — who will undoubtedly try to pick apart her story.