With James Reimer out with an upper-body injury, Gustavsson likely will start the remainder of the games.
David Steckel will be a game-time decision because of a lower-body injury.
"I've got a sheet of paper, there's about 15 different combinations I have put down there." said Leafs coach Randy Carlyle. "I would think that you are going to see Tim Connolly go to the middle with Carter Ashton and (Joey) Crabb, that is tentatively on one of those little pieces of paper."
The Flyers are without goalie Ilya Bryzgalov and defenseman Kimmo Timonen, neither of whom made the trip. Bryzgalov has a chip fracture in his right foot, while Timonen is taking a game off to treat an upper-body injury.