Four MTA workers were rushed to a hospital on Tuesday night after a crazed straphanger sprayed a mace-like substance on a subway platform at Grand Central Terminal, an agency spokesperson said.

Two customers got into a fight aboard a southbound No. 5 train as it approached Grand Central at about 7 p.m., the MTA said.

When the doors opened at the Midtown station, one of the people involved in the fight sprayed a chemical substance on the platform, the agency said.

Four MTA platform conductors ingested the spray and needed to be rushed to the Bellevue Hospital.

It was not immediately clear if anyone was arrested after the incident, police said. There was no word on any other injuries.