Downie, playing his first game for the Flyers after being acquired from the Colorado Avalanche on Thursday, was injured during a fight with Aaron Volpatti late in the second period. He received a minor for instigating, a fighting major and a misconduct.
General manager Paul Holmgren said Downie was taken to University of Pennsylvania hospital for tests and observation.
Center Vincent Lecavalier sustained facial injuries and may have lost some teeth during a third-period fight with Steve Oleksy.
Holmgren said neither player will take part in the Flyers' road game against the New Jersey Devils on Saturday.
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