Cassie, Sean “Combs”’s former girlfriend, is set to testify as one of the initial witnesses in his high-profile sex-trafficking federal trial, with her appearance potentially scheduled for Monday, according to prosecutors.

The renowned R&B artist, also known as Cassandra Ventura, will be the third witness presented by the prosecution in the case against the hip-hop icon, who stands accused of overseeing a prolonged period of sexual exploitation, said prosecutor Maurene Comey.

The first two witnesses will include an escort, and another minor witness who needs to testify Monday for logistical reasons, the feds said.

The announcement was made on Friday amidst a delay in the final phase of jury selection, which was granted by Judge Arun Subramanian until Monday morning at the request of Combs’ legal team, despite objections from the prosecution.

Combs’ lawyers had expressed concerns that more jurors would ask to leave the case after one of the prospective panelists asked to be dismissed in a letter to the court on Thursday, citing “security concerns.”

The 12 jurors and six alternates who make the cut will be sworn in Monday morning and hear each side’s opening statement in the hotly anticipated case, the judge said.

Among the most crucial evidence jurors will see at the trial is footage of Combs punching and kicking Ventura in a disturbing caught-on-camera attack at a hotel in 2016.

Prosecutors have asked Subramanian to allow Ventura, who is pregnant, to pause her testimony for a break every 90 minutes.

Combs is being held without bail in a Brooklyn lockup after the feds argued that he was a “danger to society,” and that he’d tried to contact witnesses in the case.

The feds say Combs forced women into “Freak-Offs” — drug-fueled, days-long “sexual performances” in which the rapper and producer’s ex-girlfriends would have sex with male escorts while he watched.

The überwealthy Sean John founder sometimes filmed the sexual escapades to use as leverage to keep the women compliant with his demands, according to his indictment.

The Harlem native is also accused of several assaults, including dangling one of his alleged victims over an apartment balcony.

The “I’ll Be Missing You” rapper has pleaded not guilty to charges of racketeering conspiracy, sex trafficking, and transportation to engage in prostitution.

His lawyers plan to argue during a two-month-long trial that the Freak-Offs were a “consensual” part of Combs’ admittedly kinky, but not criminal, sex life.