Porzingis, who was set to lead Latvia in the World Cup, which begins Aug. 25 in the Philippines, Japan and Indonesia, posted on social media Tuesday that a recent MRI result led to the decision not to play. He noted that it was a joint decision, made with the Latvian medical and coaching staffs along with the Celtics.
While he won't be able to play, Porzingis noted he will be present with the team and continue to support them as much as he can.
The Celtics said Wednesday that Porzingis will rehab the injury for four to six weeks and is expected to be cleared for training camp.
The 7-foot-3 Porzingis was traded to the Celtics this offseason and agreed to a two-year, $60 million extension that will tie him to Boston through the 2025-26 season at a total of $96 million.
Last season with Washington, Porzingis played in 65 games, the third most that he's played in a single season in his eight-year NBA career. He averaged a career-best 23.2 points while putting up 8.4 rebounds, 2.7 assists and 1.5 blocks. He also shot a career-high 49.8% from the field and his 38.5% 3-point percentage was the second-best mark of his career.
Porzingis was one of two current NBA players on the 16-man roster Latvia released at the end of July for the upcoming World Cup. The only other current NBA player was Davis Bertans, who was traded to the Oklahoma City Thunder this offseason.