The broken father of a young man barbarically murdered in a posh Manhattan pad after a night of partying wept uncontrollably Thursday as he relived for jurors the day his son vanished.

Pat Comunale, 57, broke into sobs the moment he took the stand as the first witness at James Rackover’s trial.

Asked by Assistant DA Peter Casolaro when he first began to worry about his boy, Joseph Comunale, the dad answered, “Sunday.”

He then pressed a white handkerchief to his face to stifle his sobs. “Give me a minute,” he asked through sobs and then added, “We spoke every day.”

He said he knew something was off when he couldn’t reach Joseph, 26, on Nov. 13, 2016, shortly before they were supposed to watch a Sunday football game.

Comunale filed a missing person’s report and a detective took him to the Grand Sutton high-rise, where they watched surveillance video of Joseph entering the building. It was the last time anyone besides the suspects saw him alive.

The dad did not yet know that Rackover, 27, and his pal Larry Dilione, who will be tried separately, allegedly beat, strangled and stabbed his son in the luxury apartment, which was paid for by jeweler-to-the-stars Jeffrey Rackover.

Authorities quickly tracked Joseph’s charred and mutilated corpse to a shallow grave in Oceanport, NJ.

After the dad’s emotional testimony, he sat beside his wife, Lisa, in the second row of the Manhattan Supreme Court gallery.

The shattered parents chose to endure the disturbing photos of Joseph Comunale’s decomposed body that were shown to jurors.

They openly sobbed as the grisly images showed the young man’s nude corpse in a partial fetal position, his face turned upward, his knees drawn toward his chest. Unable to absorb the horror any longer, Comunale’s mother dropped her gaze to the floor as her husband held her.

The Hofstra grad was discovered in a muddy hole in the woods behind a florist near where Dilione had grown up.

The courtroom was packed with the victim’s distraught friends and family.

Casolaro told jurors in opening statements that Comunale headed to Rackover’s apartment, who he’d met for the first time that day, after an evening of partying and continued to drink heavily and snort cocaine. Comunale and Dilione walked three women who were with them at the E. 59th St/ pad down to get an Uber and then returned to the apartment.

He and Dilione, 30, got into a fight, which “appeared to be over the lack of more cocaine,” Casolaro said.

Dilione then beat Comunale unconscious before he and Rackover decided to stab him to death, the prosecutor said.

“Joseph Comunale was alive and feebly trying to defend himself,” Casolaro told jurors.

The men tried to clean up the gruesome scene then tossed Comunale’s body out the fourth-floor window and stuffed him into the trunk of Jeffrey Rackover’s Mercedes Benz.

The jeweler to such notables as Oprah and Melania Trump, prosecutors described him as James Rackover’s “wealthy middle-aged companion” who was trying to “masquerade” as his father, and had leased the car for him.

“For reasons only known to them, they wanted to conceal the true nature of their relationship,” Casolaro said.

Defense lawyer Maurice Sercarz called the murder a tragedy but blamed it on Dilione, who he said viciously beat Joseph Comunale after he was rendered unconscious.

During the attack, he said, James Rackover had popped up to Jeffrey Rackover’s apartment on the 32nd floor to look for cocaine.

He suggested that it was Dilione who stabbed Comunale with a folding knife that the partygoers had used to snort cocaine earlier.

Rackover, he argued, had merely “succumbed to the need to get that body out of the apartment and assisted in that endeavor.”

Jenna Stisi testified that she had been at James Rackover’s apartment that morning partying with two friends. Rackover and Dilione had each given her a lap dance, she said.

Dilione and Comunale later walked the women downstairs to catch an Uber.

The next day, Connecticut police contacted Stisi about Comunale’s whereabouts, and she texted James Rackover to ask if he knew anything.

“Yea like the police are calling me I’m like wtf,” James Rackover callously replied. “Anyway bad timing but you me and my pal Larry should all go out sometime this weekend and do something. You seemed like a cool chick from the little I saw :)” he added, flirtatiously.

The trial continues Friday before Justice James Burke.

A third defendant, Max Gemma, who was present during the assault, will be tried last, on charges of hindering the prosecution and tampering with evidence.

Additional reporting by Olivia Bensimon