League sources told ESPN and the New York Times that Tatum was examined Wednesday and ruled out for at least the next two games at the World Cup due to the ankle ailment. He will be reevaluated Monday.
Tatum turned his ankle in the closing seconds of overtime in Team USA's 93-92 victory over Turkey on Tuesday night. Before exiting the game, he notched a double-double with 11 points and 11 rebounds in 31 minutes.
The U.S. men's basketball team will play in its final pool play game Thursday against Japan. The Americans have already advanced to the second round, and Japan has already been eliminated.
Team USA will open play in the second round Saturday. The U.S. could face elimination Monday, the same day Tatum will be reevaluated.
Through two games at the World Cup, Tatum is averaging 10.5 points per game.