A third dirt biker was busted this week in connection to the shocking beatdown of a motorist and his son over an “accident” in Harlem, cops said Wednesday.

Antwaun Joyce, 30, of Harlem, was arrested Monday and charged with three counts of robbery and one count of gang assault in connection to the March 15 road rage attack, authorities said. 

The caught-on-camera violence unfolded around 4:30 p.m. that day as the 64-year-old driver — who was heading west on West 127th Street — struck one of the bikers, who had just run a red light at Frederick Douglass Boulevard, cops said.

The crew tailed the motorist for two blocks before cutting him off at St. Nicholas Terrace, cops said.

Four of the attackers then got off their illegal rides and surrounded the car, pulling the driver and his 36-year-old son from inside, cops said.

The crew then beat and robbed them of their cellphones, credit cards and cash, according to police.

Both men were taken to St. Luke’s Hospital in stable condition.

The driver’s son later told The Post he is worried about his father, who suffered a concussion and is struggling in the aftermath of the attack. 

“I’m OK, I’m just really concerned about him, concerned about my father,” he said previously. “I want them to find them, and justice.”

Joyce has two prior arrests, one for criminal possession of a weapon from 2020, and another for driving while intoxicated from 2016, police said.

Three days before Joyce was busted, James McMurren, 29, of the Bronx, was nabbed in connection to the beatdown, cops said. 

He was charged with robbery, gang assault and assault, police said. 

The first suspect busted was Kureem Nelson, 35, also of Harlem, who was nabbed Thursday on two counts each of robbery and assault, as well as a count each of gang assault, petit larceny and criminal mischief, cops said.