The Swede, who scored the most points in his club team New Jersey during the season, has an injury that prevents him from playing in the tournament on home soil.
He will be out for up to four months, says agent Joakim Persson to the newspaper.
Bratt recently went out of the Stanley Cup playoffs in the first round with his New Jersey. The 26-year-old comes from Stockholm – where Tre Kronor will play.
He has really looked forward to playing in Stockholm. But he did not pass the medical examination and they have found an injury on the upper body, says Persson.
The Ice Hockey World Championship starts on Friday and so far 18 NHL players have said yes to playing in Tre Kronor.