Flyers coach Peter Laviolette announced the decision prior to Monday's game. He says he liked how Boucher "bailed us out of a couple of situations" in a 5-4 win Saturday.
The series is tied at one game apiece.
Boucher stopped 20 of 21 shots in taking over for Bobrovsky, who was pulled after allowing three goals on seven shots 12:30 into the game.
Boucher is the Flyers most experience goalie. He has an 18-15 career playoff record.
The Flyers will be without forward Andreas Nodl, who sustained an upper body injury Saturday.