The alleged incident occurred on Saturday night as Mario Licato, 26, was leaving a Manhattan train station, police confirmed.
"I was walking up the stairs... [The attacker] was coming down," Licato told ABC News. "Then, boom, [I] saw a fist in my face. As I was falling down the stairs, I heard, 'That's because you look exactly like Shia LaBeouf.'"
Although he did not go to the hospital, Licato said he was "knocked out cold." He also claimed the punch left him bloodied and his glasses broken.
Police say they do not have a description of the suspect, and they are treating the incident as a misdemeanor assault.