Hey, buddy, save the fighting for the fires.

An off-duty firefighter cold-cocked a retired correction officer after a car crash early Sunday, leading to a wild, allegedly drunken brawl that landed both men behind bars — and the firefighter under investigation.

It started with a bang — as the Ford Mustang carrying off-duty Bravest Daniel Woodford, 32, and his brother smashed into a utility pole at the corner of West Raleigh Avenue and Ford Place in Staten Island’s West Brighton neighborhood at around 1 a.m., police sources said.

Woodford’s brother was allegedly driving.

Hearing the crash, retired Department of Correction officer Dale Williams, 57, and his son came out of their nearby home. Woodford’s brother “admitted he [himself] was drunk and he messed up,” Williams told cops, according to sources.

In a bizarre turn of events, Williams recognized the Woodford brothers and offered to let them park their damaged car in his driveway.

But no good deed goes unpunished and, as Williams got in the car to move it for the allegedly drunken brothers, Daniel Woodford socked him in the face so hard, he fell back and hit his head on the ground, causing bleeding on his brain, police sources said.

Williams’ son began scrapping with the Woodfords while the elder Williams ran inside, grabbed a stick and wailed on Daniel Woodford’s hand, breaking the firefighter’s finger, the sources said.

Police responded and arrested Woodford and the elder Williams for assault. It took several officers to subdue Williams, and he was also charged with resisting arrest, according to the sources.

The firefighter’s brother ran away from the scene and hadn’t been caught as of Sunday night, police sources said.

Woodford — who plays quarterback on the FDNY’s football team — has previously been arrested for driving while intoxicated and felony assault, according to police sources.

The FDNY could suspend him as a result of Sunday’s incident.