Felix Sandstrom looked like he had a firm grasp on the position, but a minor injury has likely derailed him from starting the season with the Flyers.
Samuel Ersson has looked poised and sharp in net, in his limited action in the preseason, and made a strong case for being the Flyers #2.
Troy Grosenick is the third option for Tortorella. Grosenick posted a 2.0 gaa and impressive .933 save percentage over 30 appearances in the AHL last season, for the Providence Bruins.
The backup goalie position isn't always about rostering the teams second best goalie however; there are more factors involved. Those factors may affect the Flyers decision.
Age, NHL experience, contract status (one or two-way contract), development, locker room presence, team chemistry, and other such factors all require consideration as well.
Is it better to roster a veteran netminder, who isn't necessarily part of your team's long-term plan and let your younger prospects face more rubber and game action in the minors? Do you want your young tenders facing NHL caliber shots in practice everyday and learning the pace and habits of players in the show? In all honesty, the statistical differences between one back up over another will not be significant: roughly .3 to .5 in gaa and a few points in save percentage. The difference between a solid backup and an average backup is one, maybe two saves per game, or statistically one goal every two games.