(CNN) -- A Maryland man severely injured in an alleged assault at a Baltimore Orioles baseball game was revived by an off-duty state trooper at the scene who apparently didn't know immediately the victim was a childhood friend. Nathan Steelman was seated a few sections away on Wednesday night at Camden Yards when Matthew Fortese, 25, was punched in the side of the head during an apparent argument with two other men and fell off a wall, police records show. His head hit the pavement below with a loud thump. The incident apparently was triggered when the men sitting in the section behind Fortese apparently taunted him about his New York Yankees hat and threw beer on him, his brother, James, said.
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Man severely injured in altercation with two fans at Baltimore baseball game
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Off-duty trooper who performed first aid on victim realized later two were old friends
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Two men held in alleged assault
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Victim hospitalized in stable condition with head injury
@placeholder pried open his mouth and cleared his airway, allowing Fortese to breathe on his own, Steelman said.