Pelletier is scheduled for surgery next week, with the team refraining from setting a definitive return date. His injury occurred during a preseason clash with the Seattle Kraken when Marian Studenic delivered a crushing hit.
The 22-year-old Pelletier was eager for a fresh start under new coach Ryan Huska, moving on from his previous experience with Darryl Sutter. Sutter's handling of Pelletier contributed to veterans' concerns, prompting management to make changes.
In the previous season, Pelletier contributed three goals and four assists with the Flames, and an impressive 37 points in 35 AHL games with the Calgary Wranglers.