Callahan's tally in the second period staked the Rangers to a 2-0 lead and New York went on to win a second straight game.
The Rangers' right wing was hurt during a fight with the Flyers' Maxime Talbot in the next period when he was yanked down to the ice and was helped off with what appeared to be a shoulder injury.
Michael Del Zotto also scored and Henrik Lundqvist made 26 saves in the win.
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