A 54-year-old man was slashed by an apparent stranger in an unprovoked attack on a Brooklyn subway platform early Thursday, cops said. 

The victim had just gotten off an R train at the 95th Street station in Bay Ridge around 5:45 a.m. when another man approached him on the platform and slashed him on the collarbone with a switchblade, police said. 

The assailant didn’t say a word during the attack, cops said.

The victim was taken to NYU Langone Hospital — Brooklyn, where he was listed in stable condition. 

The suspect, believed to be in his 30s, ran off and hadn’t been arrested by later Thursday morning.