Fitzpatrick was released from his professional tryout with the Lightning on Saturday and returned to AHL Syracuse.
The Panthers promoted Fitzpatrick on Sunday, per CapFriendly.
Fitzpatrick signed a contract with the Panthers on Thursday and was subsequently placed on waivers, per Elliotte Friedman of Sportsnet.
Fitzpatrick was reassigned from the taxi squad to AHL Charlotte on Saturday.
Fitzpatrick signed a one-year, two-way contract with the Panthers and was added to the taxi squad Friday.
Fitzpatrick agreed to a professional tryout agreement with the Panthers ahead of training camp, per CapFriendly.
Fitzpatrick will not receive a qualifying offer from the Blues on Monday and will become an unrestricted free agent, Jeremy Rutherford of The Athletic reports.
The Blues demoted Fitzpatrick back to AHL San Antonio on Saturday, Jim Thomas of The St. Louis Post-Dispatch reports.
The Blues recalled Fitzpatrick from AHL San Antonio on Sunday.
Fitzpatrick will compete for the No. 2 role with AHL San Antonio, Lou Korac of NHL.com reports.