BALTIMORE -- A man suffered a serious head injury Sunday after an altercation at M&T Bank Stadium with two Oakland Raiders fans, who were arrested, Baltimore police told The Baltimore Sun.

Joseph Bauer, 55, is in critical condition with a subdural hematoma, according to his sister. Doctors had told the family he has a 30 percent chance of survival, his sister said.

Police identified the men charged as Scott Smith, 28, of Mount Vernon, N.Y., and Andrew Nappi, 31, of Eastchester of N.Y. Both were charged with first- and second-degree assault.

"Our sympathies and prayers go out to Mr. Joseph Bauer, his wife Sharon and the rest of his family. We have reached out to the family and have received a report on Mr. Bauer's condition," the Ravens said in a statement.

"We are deeply concerned about this assault and are learning as much as we can about it. Safety for our fans is a top priority. Confrontational and inflammatory behavior is never tolerated and is unacceptable at Ravens home games."

Bauer got into a verbal argument with a group of Raiders fans near a concession stand toward the end of the Ravens' 28-27 loss, according to his sister. Her brother's head hit the concrete after he was struck, knocking him unconscious and causing a serious head injury, she said.