The 33-year-old man, who was wearing a Lions football jersey, said he was walking to the Southeastern Pennsylvania Transportation Authority station near Lincoln Financial Field to catch a train home after the game when he was harassed by Eagles fans.
"I tried to keep my head down and avoid them," the man, who did not want his identify released, said of the group of men began throwing snowballs at him. "I didn't want to give them the satisfaction."
He said six men tried to block his path, and one man allegedly slapped him on the side of the head. The alleged victim said he punched one of his attackers, knocking him to the ground, but the other men began punching him in the head.
"I felt like I was being choked and punched," he said.
The man told police when he came to, another Eagles fan was standing over him, trying to help him to the train station. He said the Good Samaritan threw his Eagles jersey in the trash in disgust over what happened.
The alleged victim said he was treated at the hospital Monday for a concussion and other minor injuries, the Philadelphia Inquirer reported.
Capt. Laurence Nodiff, commander of South Detectives, said police were searching for surveillance footage of the incident.
"These despicable attacks on fans who are rooting for other teams is something we don't take lightly, and we're not going to tolerate it," he said.