A panhandler with a lengthy rap sheet was busted for allegedly stabbing an elderly man at the Herald Square subway station — and punching another straphanger on a train less than a day later, cops and sources said Tuesday.

David Trotman, 38, was charged with felony assault for the 11:30 p.m. Sunday attack on 76-year-old Iqbal Ahmed, who remained hospitalized after nearly getting stabbed in the heart by the crazed stranger.

The senior was attacked after reportedly refusing to give the panhandler cash, spurring an argument on the steps leading to the subway station at West 35th Street and Sixth Avenue, cops said. 

Trotman allegedly stabbed the victim once in the right side of his chest by his armpit, authorities said.

Ahmed was taken to Bellevue Hospital, where he was listed in stable condition. 

Then around 2:50 p.m. Monday, Trotman punched a 42-year-old man multiple times on a northbound A train approaching 23rd Street, cops said. 

Cops caught up to him at the Times Square station, where he was arrested and charged with misdemeanor assault, the sources said. 

Police said they then linked Trotman — who has a slew of arrests dating back to at least 2017 — to the attack on Ahmed a day prior.

Trotman was also charged Monday with forcible touching for allegedly grabbing the buttocks of a 21-year-old woman walking at Wall Street and William Street in Lower Manhattan back on July 12, cops and sources said. 

Previously, he was arrested April 27 in Queens Village for allegedly denting the door to a shed in the backyard of a home there, according to the criminal complaint against him.

He was arraigned on charges of criminal mischief and criminal trespass, online records show. 

A temporary order of protection was issued, and Trotman was released with non-monetary bail conditions, according to the records. His next court date in that case is September 27.

On March 11, he was arrested in Brooklyn for evading the subway fare, cops said. 

He was also nabbed in Queens in January 2017 for grand larceny, police said. 

In that case, he stole a woman’s minivan and then struck one moving car — and four parked ones — while trying to get away from cops, who had stopped him, according to the criminal complaint against him. 

He pleaded guilty to grand larceny in the fourth degree in April 2017 and was sentenced to up to nine months behind bars, according to the Queens District Attorney’s Office. 

He served about two years in state prison — from November 2018 to December 2020 — on an unauthorized use of a motor vehicle conviction out of Suffolk County, Department of Correction records show.

Trotman is also wanted in Queens for two separate orders-of-protection violations from earlier this month, the sources said. 

In the first case, from August 6, he stood on the front lawn of the same Queens Village home where he allegedly damaged the shed door — and threw a bucket of urine onto the front window, the sources said.  

Then on Saturday, he returned to that home and threw an unspecified liquid onto the victim’s driveway, according to the sources. 

He was awaiting arraignment in the Manhattan subway crimes Tuesday.