A 57-year-old man is clinging to life after he was struck by a hit-and-run driver in Brooklyn late Wednesday, cops said. 

The victim was attempting to cross Avenue D near East 38th Street in East Flatbush midblock around 10:10 p.m. when he was struck by an oncoming Mercedes-Benz, according to police. 

He was left with head trauma and a broken right leg, and taken to the Kings County Hospital Center in critical condition, authorities said. 

The driver fled, and had not been arrested by Thursday afternoon.