The Flyers acquired Gagner in an off-season trade with the Arizona Coyotes that saw defenceman Nicklas Grossmann and the remainder of Hall of Famer Chris Pronger’ contract. The Coyotes also received a conditional draft pick.
Gagner was selected in the first-round, sixth overall, by the Edmonton Oilers in the 2007 NHL Draft.
The 26-year-old has scored two goals and totaled five points in 18 games with the Flyers this season. He missed a chunk of time after suffering a concussion in a game versus the Carolina Hurricanes on November 23.
Teams have until noon ET Wednesday to claim Gagner. He will be cleared to be sent to the Flyers' AHL affiliate Lehigh Valley Phantoms if he goes unclaimed.