A source told ESPN’s Adrian Wojnarowski that the expected recovery time is between six and 12 months and that Gallinari is determined to try to return late in the 2022-23 NBA season.
Gallinari previously suffered a torn left ACL in April 2013 that ended up requiring two surgeries and kept him out of the NBA until the 2014-15 season.
The 34-year-old Gallinari was injured Saturday during a FIBA World Cup qualifying game against Georgia. He grabbed his left knee after a bounce pass in the lane before hobbling over to the sideline, holding the back of the knee as trainers rushed to his aid. Gallinari then limped to the locker room with the help of a staff member and a teammate.
The Italian team had said last weekend that Gallinari had suffered a torn meniscus.
Gallinari had signed with the Celtics on July 12 via the midlevel exception and was being counted on for depth as Boston looks to return to the NBA Finals.
A first-round draft pick of the New York Knicks in 2008, Gallinari has averaged 15.6 points and 4.7 rebounds per game in his career while also playing for the Denver Nuggets, LA Clippers, Oklahoma City Thunder and Atlanta Hawks.