Johnson was acquired by the Flyers from the Buffalo Sabres at this year's trade deadline and was clearly a depth move. The Flyers just traded Sean Walker and had 3 other defensemen on injured reserve. Johnson, 36, is an unrestricted free agent this offseason, so it would not make sense for the Flyers to re-sign Johnson, especially with the plethora of young defensemen they have. Then, there is Staal, he was signed by the Flyers last offseason to a one-year contract, but he is now 37, and was a healthy scratch several games this year. He was forced into action due to the trade of Sean Walker and the other injured defenseman. Again, it would not make sense to re-sign him either so do not expect him to be back.
Lastly, there is Peterson, unlike, Johnson and Staal, Peterson
is not an unrestricted free agent this offseason. Peterson signed a three-year contract with the Los Angeles Kings and has one year left on the deal with a $5-million cap hit. The Flyers will have to buy his contract out this offseason, which would save them some cap space. This seems likely as Peterson performed so poorly, they were forced to send him to the minors in favor of Felix Sandstrom. On the year, Peterson played in five games with 3.90 GAA and .864 save percentage. The Flyers will most likely have the goalie tandem of Sam Ersson and Ivan Fedotov next season so there is no reason to bring back Peterson.