Mourners at Jordan Neely’s funeral remembered the 30-year-old homeless man as a mellow guy and a gifted dancer who’d fallen on hard times in the years before his death at the hands of Daniel Penny, a former Marine now charged with manslaughter.

Neely — a Michael Jackson-impersonating street performer with a long history of mental illness and police run-ins — was not always that way, childhood friend Rocco Polanco told The Post at the Mount Neboh Baptist Church in Harlem, where Neely’s funeral was held.

“Jordan was an amazing dancer – phenomenal,” said Polanco, of the Bronx. “He was a reflection of Michael Jackson – he had every move down pat, and even had the same facial structure.”

Polanco, 19, who showed up at the ceremony wearing a black-and-red, Jackson-inspired suit, recalled Neely as a mellow kid always known for his uncanny ability to move just like the King of Pop.

The two hung out together near the famed Apollo Theater on 125th Street in Harlem, Polanco said.

And when the legendary pop singer passed away in 2009, it was Neely who lifted them up through his skilled impersonation.

“He made us all feel good when Michael Jackson died,” Polanco said. “People came to Times Square just to see [Jordan].”

But Neely had gone downhill in recent years, a descent friends and family have attributed to the brutal murder of his mother in 2007. Neely sank into a deep depression and was never properly treated, they said.

Polanco said he saw Neely a couple years ago. He could tell his old friend had fallen on hard times.

“I gave him all my money,” Polanco said. “He wasn’t doing too good. I reminded him that we used to dance, and he smirked for a second. Then he went back to a blank face, like he was ashamed.”

His slide continued until earlier this month, when witnesses say the homeless man went on an explosive tirade on an F Train in Manhattan on May 1. He allegedly threw garbage at other straphangers, threatened them and said he was willing to “[take] a bullet” or go to jail.

Penny grabbed Neely from behind and placed him in a chokehold, and a pair of other passengers helped the former infantry squad leader restrain the struggling Neely.

But the chokehold allegedly ended up killing him – the city medical examiner ruled Neely’s death a homicide, and noted that he died from “compression of neck (chokehold).”

Penny’s defense team claims he wasn’t trying to kill Neely when he grabbed him — he was merely trying to protect himself and others from a threatening homeless man who had scores of prior arrests.

Neely’s family has said Penny should be tried for murder, not manslaughter.

Penny remains free on $100,000 bail.

Noel McDonald, a 50-year-old Brooklyn man, said he didn’t know Neely’s family but felt compelled to pay his last respects.

“That brother in there was talented,” McDonald told The Post. “He was gifted. And sure he was homeless – he was homeless because he was carrying mental pain from his mother’s murder.”

“All he wanted was food and help and he was choked to death for it,” McDonald continued. ““Nobody deserves that. I get it, sometimes people lash out. But that’s not an excuse to kill them … This is about justice.”